Squashed 'tz/' changes from 9c175ec6c..a816a5c4d

efc5c0619 Release 2020e b804a741d Improve doc of zic coalescing zone+DST transitions c8891f390 Cite publication of Volgograd change 316c1598e Correct LMT and pre-1919 transitions for Nigeria 3dcdea78d Fix NEWS typo c983a0fb7 Document zic coalescing zone+DST transitions ce7b1bbc7 Seychelles switched from LMT to +04 on 1907-01-01 b980f1cac Model Turks & Caicos time 2015-2018 as AST ff90fc93a Fix Vanuatu DST in 1973-1974 and 1984 transition 7c7419c6a Volgograd change likely December 27, not 20 0b5ae1fb7 Fix some errors in recent Bahamas changes cd1769fe6 Fix Ghana again, for 1942 through 1946 3831c591e Fix Volgograd label in {zone,zone1970}.tab adf4d8d35 Fix several pre-1946 transitions for Bahamas 0415d0e5f Re-fix Ghana typo for 1919/1920 6e7558f19 Fix Ghana typo for 1919/1920 271d9438b Volgograd switches from +04 to +03 on 12-20 02:00 a499dd6e0 * northamerica: Add URL for Yukon OIC 1980/02 7cc6d7c00 Fix several pre-1957 transitions for Ghana 17acee8cb Fix several pre-1957 transitions for Bermuda 1aca4cad3 Fix several pre-1972 transitions for Australia a47ef9c71 * tz-link.html: Use <abbr> more systematically. 48e68fbfd Document "right" seconds better beba17f43 Fix mistaken Belize interpretation d7e93bdba Fix several Belize transitions 1942/1968 b231fbdb5 Port 'make rearguard_tarballs' to Solaris 10 8b21cc5d2 Fix Israel and Palestine transitions 1940/1985 52ba05422 Fix zone*.tab Yukon comment columns b106a6e84 leapseconds now says why NIST, not IERS eff0719a7 Fix Kenya transitions 1908/1960 78422f077 Use better fallback for unknown $(VERSION) ac029805c * etcetera: Update comment in the light of Neil Fuller’s comments. e4645c40a Port to downstream HP-UX-style ‘make’ git-subtree-dir: tz git-subtree-split: a816a5c4de427cae12477455dea2bc4eb990b2c9
author: Stuart Bishop <stuart.bishop@canonical.com> 2020-12-25 07:42:52 +1100
committer: Stuart Bishop <stuart.bishop@canonical.com> 2020-12-25 07:42:52 +1100
commit: aaef58a8e40d7e6bd70f2d4ce347caa772510e59 (patch)
tree: f30c29def341fdcb502e575c5a9441e4567a55c2
parent: a4a62d8d41eea2df3759cbcdbd9100a72e8c28c7 (diff)
download: pytz-git-aaef58a8e40d7e6bd70f2d4ce347caa772510e59.tar.gz
16 files changed, 863 insertions, 174 deletions
diff --git a/Makefile b/Makefile
index 40b81d1..5064a19 100644
--- a/Makefile
+++ b/Makefile
@@ -583,11 +583,19 @@ INSTALL:	ALL install date.1
 		cp date '$(DESTDIR)$(BINDIR)/.'
 		cp -f date.1 '$(DESTDIR)$(MANDIR)/man1/.'
 
+# Calculate version number from git, if available.
+# Otherwise, use $(VERSION) unless it is "unknown" and there is already
+# a 'version' file, in which case reuse the existing 'version' contents
+# and append "-dirty" if the contents do not already end in "-dirty".
 version:	$(VERSION_DEPS)
 		{ (type git) >/dev/null 2>&1 && \
 		  V=`git describe --match '[0-9][0-9][0-9][0-9][a-z]*' \
 				--abbrev=7 --dirty` || \
-		  V='$(VERSION)'; } && \
+		  if test '$(VERSION)' = unknown && V=`cat $@`; then \
+		    case $$V in *-dirty);; *) V=$$V-dirty;; esac; \
+		  else \
+		    V='$(VERSION)'; \
+		  fi; } && \
 		printf '%s\n' "$$V" >$@.out
 		mv $@.out $@
 
@@ -872,11 +880,34 @@ $(MANTXTS):	workman.sh
 		LC_ALL=C sh workman.sh `expr $@ : '\(.*\)\.txt$$'` >$@.out
 		mv $@.out $@
 
+# Set file timestamps deterministically if possible,
+# so that tarballs containing the timestamps are reproducible.
+#
+# '$(SET_TIMESTAMP_N) N DEST A B C ...' sets the timestamp of the
+# file DEST to the maximum of the timestamps of the files A B C ...,
+# plus N if GNU ls and touch are available.
+SET_TIMESTAMP_N = sh -c '\
+  n=$$0 dest=$$1; shift; \
+  touch -cmr `ls -t "$$@" | sed 1q` "$$dest" && \
+  if test $$n != 0 && \
+     lsout=`ls -n --time-style="+%s" "$$dest" 2>/dev/null`; then \
+    set x $$lsout && \
+    touch -cmd @`expr $$7 + $$n` "$$dest"; \
+  else :; fi'
+# If DEST depends on A B C ... in this Makefile, callers should use
+# $(SET_TIMESTAMP_DEP) DEST A B C ..., for the benefit of any
+# downstream 'make' that considers equal timestamps to be out of date.
+# POSIX allows this 'make' behavior, and HP-UX 'make' does it.
+# If all that matters is that the timestamp be reproducible
+# and plausible, use $(SET_TIMESTAMP).
+SET_TIMESTAMP = $(SET_TIMESTAMP_N) 0
+SET_TIMESTAMP_DEP = $(SET_TIMESTAMP_N) 1
+
 # Set the timestamps to those of the git repository, if available,
 # and if the files have not changed since then.
-# This uses GNU 'touch' syntax 'touch -d@N FILE',
-# where N is the number of seconds since 1970.
-# If git or GNU 'touch' is absent, don't bother to sync with git timestamps.
+# This uses GNU 'ls --time-style=+%s', which outputs the seconds count,
+# and GNU 'touch -d@N FILE', where N is the number of seconds since 1970.
+# If git or GNU is absent, don't bother to sync with git timestamps.
 # Also, set the timestamp of each prebuilt file like 'leapseconds'
 # to be the maximum of the files it depends on.
 set-timestamps.out: $(EIGHT_YARDS)
@@ -894,16 +925,16 @@ set-timestamps.out: $(EIGHT_YARDS)
 		    fi || exit; \
 		  done; \
 		fi
-		touch -cmr `ls -t $(LEAP_DEPS) | sed 1q` leapseconds
+		$(SET_TIMESTAMP_DEP) leapseconds $(LEAP_DEPS)
 		for file in `ls $(MANTXTS) | sed 's/\.txt$$//'`; do \
-		  touch -cmr `ls -t $$file workman.sh | sed 1q` $$file.txt || \
+		  $(SET_TIMESTAMP_DEP) $$file.txt $$file workman.sh || \
 		    exit; \
 		done
-		touch -cmr `ls -t $(TZDATA_ZI_DEPS) | sed 1q` tzdata.zi
-		touch -cmr `ls -t $(VERSION_DEPS) | sed 1q` version
+		$(SET_TIMESTAMP_DEP) version $(VERSION_DEPS)
+		$(SET_TIMESTAMP_DEP) tzdata.zi $(TZDATA_ZI_DEPS)
 		touch $@
 set-tzs-timestamp.out: $(TZS)
-		touch -cmr `ls -t $(TZS_DEPS) | sed 1q` $(TZS)
+		$(SET_TIMESTAMP_DEP) $(TZS) $(TZS_DEPS)
 		touch $@
 
 # The zics below ensure that each data file can stand on its own.
@@ -981,7 +1012,7 @@ tarballs rearguard_tarballs traditional_tarballs \
 signatures rearguard_signatures traditional_signatures: \
   version set-timestamps.out rearguard.zi
 		VERSION=`cat version` && \
-		$(MAKE) VERSION="$$VERSION" $@_version
+		$(MAKE) AWK='$(AWK)' VERSION="$$VERSION" $@_version
 
 # These *_version rules are intended for use if VERSION is set by some
 # other means.  Ordinarily these rules are used only by the above
@@ -1018,7 +1049,7 @@ tzdata$(VERSION)-rearguard.tar.gz: rearguard.zi set-timestamps.out
 		for f in $(TDATA) $(PACKRATDATA); do \
 		  rearf=tzdata$(VERSION)-rearguard.dir/$$f; \
 		  $(AWK) -v DATAFORM=rearguard -f ziguard.awk $$f >$$rearf && \
-		  touch -cmr `ls -t ziguard.awk $$f` $$rearf || exit; \
+		  $(SET_TIMESTAMP_DEP) $$rearf ziguard.awk $$f || exit; \
 		done
 		sed '1s/$$/-rearguard/' \
 		  <version >tzdata$(VERSION)-rearguard.dir/version
@@ -1037,7 +1068,7 @@ tzdb-$(VERSION).tar.lz: set-timestamps.out set-tzs-timestamp.out
 		rm -fr tzdb-$(VERSION)
 		mkdir tzdb-$(VERSION)
 		ln $(ENCHILADA) tzdb-$(VERSION)
-		touch -cmr `ls -t tzdb-$(VERSION)/* | sed 1q` tzdb-$(VERSION)
+		$(SET_TIMESTAMP) tzdb-$(VERSION) tzdb-$(VERSION)/*
 		LC_ALL=C && export LC_ALL && \
 		tar $(TARFLAGS) -cf - tzdb-$(VERSION) | lzip -9 >$@.out
 		mv $@.out $@
@@ -1079,8 +1110,6 @@ strftime.o:	private.h tzfile.h
 zdump.o:	version.h
 zic.o:		private.h tzfile.h version.h
 
-.KEEP_STATE:
-
 .PHONY: ALL INSTALL all
 .PHONY: check check_time_t_alternatives
 .PHONY: check_web check_zishrink
diff --git a/NEWS b/NEWS
index 328face..6014b45 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,51 @@
 News for the tz database
 
+Release 2020e - 2020-12-22 15:14:34 -0800
+
+  Briefly:
+    Volgograd switches to Moscow time on 2020-12-27 at 02:00.
+
+  Changes to future timestamps
+
+    Volgograd changes time zone from +04 to +03 on 2020-12-27 at 02:00.
+    (Thanks to Alexander Krivenyshev and Stepan Golosunov.)
+
+  Changes to past timestamps
+
+    Correct many pre-1986 transitions, fixing entries originally
+    derived from Shanks.  The fixes include:
+      - Australia: several 1917 through 1971 transitions
+      - Bahamas: several 1941 through 1945 transitions
+      - Bermuda: several 1917 through 1956 transitions
+      - Belize: several 1942 through 1968 transitions
+      - Ghana: several 1915 through 1956 transitions
+      - Israel and Palestine: several 1940 through 1985 transitions
+      - Kenya and adjacent: several 1908 through 1960 transitions
+      - Nigeria and adjacent: correcting LMT in Lagos, and several 1905
+        through 1919 transitions
+      - Seychelles: the introduction of standard time in 1907, not 1906
+      - Vanuatu: DST in 1973-1974, and a corrected 1984 transition
+    (Thanks to P Chan.)
+
+    Because of the Australia change, Australia/Currie (King Island) is
+    no longer needed, as it is identical to Australia/Hobart for all
+    timestamps since 1970 and was therefore created by mistake.
+    Australia/Currie has been moved to the 'backward' file and its
+    corrected data moved to the 'backzone' file.
+
+  Changes to past time zone abbreviations and DST flags
+
+    To better match legislation in Turks and Caicos, the 2015 shift to
+    year-round observance of -04 is now modeled as AST throughout before
+    returning to Eastern Time with US DST in 2018, rather than as
+    maintaining EDT until 2015-11-01.  (Thanks to P Chan.)
+
+  Changes to documentation
+
+    The zic man page now documents zic's coalescing of transitions
+    when a zone falls back just before DST springs forward.
+
+
 Release 2020d - 2020-10-21 11:24:13 -0700
 
   Briefly:
diff --git a/africa b/africa
index 566436b..59cf501 100644
--- a/africa
+++ b/africa
@@ -386,36 +386,87 @@ Zone	Africa/Cairo	2:05:09 -	LMT	1900 Oct
 
 # Ghana
 
-# From Paul Eggert (2018-01-30):
-# Whitman says DST was observed from 1931 to "the present";
-# Shanks & Pottenger say 1936 to 1942 with 20 minutes of DST,
-# with transitions on 09-01 and 12-31 at 00:00.
-# Page 33 of Parish GCB, Colonial Reports - Annual. No. 1066. Gold
-# Coast. Report for 1919. (March 1921), OCLC 784024077
-# http://libsysdigi.library.illinois.edu/ilharvest/africana/books2011-05/5530214/5530214_1919/5530214_1919_opt.pdf
-# lists the Determination of the Time Ordinance, 1919, No. 18,
-# "to advance the time observed locally by the space of twenty minutes
-# during the last four months of each year; the object in view being
-# to extend during those months the period of daylight-time available
-# for evening recreation after office hours."
-# Vanessa Ogle, The Global Transformation of Time, 1870-1950 (2015), p 33,
-# writes "In 1919, the Gold Coast (Ghana as of 1957) made Greenwich
-# time its legal time and simultaneously legalized a summer time of
-# UTC - 00:20 minutes from March to October."; a footnote lists
-# the ordinance as being dated 1919-11-24.
-# The Crown Colonist, Volume 12 (1942), p 176, says "the Government
-# intend advancing Gold Coast time half an hour ahead of G.M.T.
-# The actual date of the alteration has not yet been announced."
-# These sources are incomplete and contradictory.  Possibly what is
-# now Ghana observed different DST regimes in different years.  For
-# lack of better info, use Shanks except treat the minus sign as a
-# typo, and assume DST started in 1920 not 1936.
+# From P Chan (2020-11-20):
+# Interpretation Amendment Ordinance, 1915 (No.24 of 1915) [1915-11-02]
+# Ordinances of the Gold Coast, Ashanti, Northern Territories 1915, p 69-71
+# https://books.google.com/books?id=ErA-AQAAIAAJ&pg=PA70
+# This Ordinance added "'Time' shall mean Greenwich Mean Time" to the
+# Interpretation Ordinance, 1876.
+#
+# Determination of the Time Ordinance, 1919 (No. 18 of 1919) [1919-11-24]
+# Ordinances of the Gold Coast, Ashanti, Northern Territories 1919, p 75-76
+# https://books.google.com/books?id=MbA-AQAAIAAJ&pg=PA75
+# This Ordinance removed the previous definition of time and introduced DST.
+#
+# Time Determination Ordinance (Cap. 214)
+# The Laws of the Gold Coast (including Togoland Under British Mandate)
+# Vol. II (1937), p 2328
+# https://books.google.com/books?id=Z7M-AQAAIAAJ&pg=PA2328
+# Revised edition of the 1919 Ordinance.
+#
+# Time Determination (Amendment) Ordinance, 1940 (No. 9 of 1940) [1940-04-06]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1940, p 22
+# https://books.google.com/books?id=1ao-AQAAIAAJ&pg=PA22
+# This Ordinance changed the forward transition from September to May.
+#
+# Defence (Time Determination Ordinance Amendment) Regulations, 1942
+# (Regulations No. 6 of 1942) [1942-01-31, commenced on 1942-02-08]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1942, p 48
+# https://books.google.com/books?id=Das-AQAAIAAJ&pg=PA48
+# These regulations advanced the [standard] time by thirty minutes.
+#
+# Defence (Time Determination Ordinance Amendment (No.2)) Regulations,
+# 1942 (Regulations No. 28 of 1942) [1942-04-25]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1942, p 87
+# https://books.google.com/books?id=Das-AQAAIAAJ&pg=PA87
+# These regulations abolished DST and changed the time to GMT+0:30.
+#
+# Defence (Revocation) (No.4) Regulations, 1945 (Regulations No. 45 of
+# 1945) [1945-10-24, commenced on 1946-01-06]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1945, p 256
+# https://books.google.com/books?id=9as-AQAAIAAJ&pg=PA256
+# These regulations revoked the previous two sets of Regulations.
+#
+# Time Determination (Amendment) Ordinance, 1945 (No. 18 of 1945) [1946-01-06]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1945, p 69
+# https://books.google.com/books?id=9as-AQAAIAAJ&pg=PA69
+# This Ordinance abolished DST.
+#
+# Time Determination (Amendment) Ordinance, 1950 (No. 26 of 1950) [1950-07-22]
+# Annual Volume of the Laws of the Gold Coast:
+# Containing All Legislation Enacted During Year 1950, p 35
+# https://books.google.com/books?id=e60-AQAAIAAJ&pg=PA35
+# This Ordinance restored DST but with thirty minutes offset.
+#
+# Time Determination Ordinance (Cap. 264)
+# The Laws of the Gold Coast, Vol. V (1954), p 380
+# https://books.google.com/books?id=Mqc-AQAAIAAJ&pg=PA380
+# Revised edition of the Time Determination Ordinance.
+#
+# Time Determination (Amendment) Ordinance, 1956 (No. 21 of 1956) [1956-08-29]
+# Annual Volume of the Ordinances of the Gold Coast Enacted During the
+# Year 1956, p 83
+# https://books.google.com/books?id=VLE-AQAAIAAJ&pg=PA83
+# This Ordinance abolished DST.
+
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Ghana	1920	1942	-	Sep	 1	0:00	0:20	-
-Rule	Ghana	1920	1942	-	Dec	31	0:00	0	-
+Rule	Ghana	1919	only	-	Nov	24	0:00	0:20	+0020
+Rule	Ghana	1920	1942	-	Jan	 1	2:00	0	GMT
+Rule	Ghana	1920	1939	-	Sep	 1	2:00	0:20	+0020
+Rule	Ghana	1940	1941	-	May	 1	2:00	0:20	+0020
+Rule	Ghana	1950	1955	-	Sep	 1	2:00	0:30	+0030
+Rule	Ghana	1951	1956	-	Jan	 1	2:00	0	GMT
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone	Africa/Accra	-0:00:52 -	LMT	1918
-			 0:00	Ghana	GMT/+0020
+Zone	Africa/Accra	-0:00:52 -	LMT	1915 Nov  2
+			 0:00	Ghana	%s	1942 Feb  8
+			 0:30	-	+0030	1946 Jan  6
+			 0:00	Ghana	%s
 
 # Guinea
 # See Africa/Abidjan.
@@ -433,11 +484,54 @@ Zone	Africa/Bissau	-1:02:20 -	LMT	1912 Jan  1  1:00u
 			 0:00	-	GMT
 
 # Kenya
+
+# From P Chan (2020-10-24):
+#
+# The standard time of GMT+2:30 was adopted in the East Africa Protectorate....
+# [The Official Gazette, 1908-05-01, p 274]
+# https://books.google.com/books?id=e-cAC-sjPSEC&pg=PA274
+#
+# At midnight on 30 June 1928 the clocks throughout Kenya was put forward
+# half an hour by the Alteration of Time Ordinance, 1928.
+# https://gazettes.africa/archive/ke/1928/ke-government-gazette-dated-1928-05-11-no-28.pdf
+# [Ordinance No. 11 of 1928, The Offical Gazette, 1928-06-26, p 813]
+# https://books.google.com/books?id=2S0S6os32ZUC&pg=PA813
+#
+# The 1928 ordinance was repealed by the Alteration of Time (repeal) Ordinance,
+# 1929 and the time was restored to GMT+2:30 at midnight on 4 January 1930.
+# [Ordinance No. 97 of 1929, The Official Gazette, 1929-12-31, p 2701]
+# https://books.google.com/books?id=_g18jIZQlwwC&pg=PA2701
+#
+# The Alteration of Time Ordinance, 1936 changed the time to GMT+2:45
+# and repealed the previous ordinance at midnight on 31 December 1936.
+# [The Official Gazette, 1936-07-21, p 705]
+# https://books.google.com/books?id=K7j41z0aC5wC&pg=PA705
+#
+# The Defence (Amendment of Laws No. 120) Regulations changed the time
+# to GMT+3 at midnight on 31 July 1942.
+# [Kenya Official Gazette Supplement No. 32, 1942-07-21, p 331]
+# https://books.google.com/books?hl=zh-TW&id=c_E-AQAAIAAJ&pg=PA331
+# The provision of the 1936 ordinance was not repealed and was later
+# incorporated in the Interpretation and General Clauses Ordinance in 1948.
+# Although it was overridden by the 1942 regulations.
+# [The Laws of Kenya in force on 1948-09-21, Title I, Chapter 1, 31]
+# https://dds.crl.edu/item/217517 (p.101)
+# In 1950 the Interpretation and General Clauses Ordinance was amended to adopt
+# GMT+3 permanently as the 1942 regulations were due to expire on 10 December.
+# https://books.google.com/books?id=jvR8mUDAwR0C&pg=PA787
+# [Ordinance No. 44 of 1950, Kenya Ordinances 1950, Vol. XXIX, p 294]
+# https://books.google.com/books?id=-_dQAQAAMAAJ&pg=PA294
+
+# From Paul Eggert (2020-10-24):
+# The 1908-05-01 announcement does not give an effective date,
+# so just say "1908 May".
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone	Africa/Nairobi	2:27:16	-	LMT	1928 Jul
-			3:00	-	EAT	1930
-			2:30	-	+0230	1940
-			2:45	-	+0245	1960
+Zone	Africa/Nairobi	2:27:16	-	LMT	1908 May
+			2:30	-	+0230	1928 Jun 30 24:00
+			3:00	-	EAT	1930 Jan  4 24:00
+			2:30	-	+0230	1936 Dec 31 24:00
+			2:45	-	+0245	1942 Jul 31 24:00
 			3:00	-	EAT
 Link Africa/Nairobi Africa/Addis_Ababa	 # Ethiopia
 Link Africa/Nairobi Africa/Asmara	 # Eritrea
@@ -1224,8 +1318,69 @@ Zone	Africa/Windhoek	1:08:24 -	LMT	1892 Feb 8
 # See Africa/Lagos.
 
 # Nigeria
+
+# From P Chan (2020-12-03):
+# GMT was adopted as the standard time of Lagos on 1905-07-01.
+# Lagos Weekly Record, 1905-06-24, p 3
+# http://ddsnext.crl.edu/titles/31558#?c=0&m=668&s=0&cv=2&r=0&xywh=1446%2C5221%2C1931%2C1235
+# says "It is officially notified that on and after the 1st of July 1905
+# Greenwich Mean Solar Time will be adopted thought the Colony and
+# Protectorate, and that it will be necessary to put all clocks 13 minutes and
+# 35 seconds back, recording local mean time."
+#
+# It seemed that Lagos returned to LMT on 1908-07-01.
+# [The Lagos Standard], 1908-07-01, p 5
+# http://ddsnext.crl.edu/titles/31556#?c=0&m=78&s=0&cv=4&r=0&xywh=-92%2C3590%2C3944%2C2523
+# says "Scarcely have the people become accustomed to this new time, when
+# another official notice has now appeared announcing that from and after the
+# 1st July next, return will be made to local mean time."
+#
+# From P Chan (2020-11-27):
+# On 1914-01-01, standard time of GMT+0:30 was adopted for the unified Nigeria.
+# Colonial Reports - Annual. No. 878. Nigeria. Report for 1914. (April 1916),
+# p 27
+# https://libsysdigi.library.illinois.edu/ilharvest/Africana/Books2011-05/3064634/3064634_1914/3064634_1914_opt.pdf#page=27
+# "On January 1st [1914], a universal standard time for Nigeria was adopted,
+# viz., half an hour fast on Greenwich mean time, corresponding to the meridian
+# 7 [degrees] 30' E. long."
+# Lloyd's Register of Shipping (1915) says "Hitherto the time observed in Lagos
+# was the local mean time. On 1st January, 1914, standard time for the whole of
+# Nigeria was introduced ... Lagos time has been advanced about 16 minutes
+# accordingly."
+#
+# In 1919, standard time was changed to GMT+1.
+# Interpretation Ordinance (Cap 2)
+# The Laws of Nigeria, Containing the Ordinances of Nigeria, in Force on the
+# 1st Day of January, 1923, Vol.I [p 16]
+# https://books.google.com/books?id=BOMrAQAAMAAJ&pg=PA16
+# "The expression 'Standard time' means standard time as used in Nigeria:
+# namely, 60 minutes in advance of Greenwich mean time.  (As amended by 18 of
+# 1919, s. 2.)"
+# From Tim Parenti (2020-12-10):
+# The Lagos Weekly Record, 1919-09-20, p 3 details discussion on the first
+# reading of this Bill by the Legislative Council of the Colony of Nigeria on
+# Thursday 1919-08-28:
+# http://ddsnext.crl.edu/titles/31558?terms&item_id=303484#?m=1118&c=1&s=0&cv=2&r=0&xywh=1261%2C3408%2C2994%2C1915
+# "The proposal is that the Globe should be divided into twelve zones East and
+# West of Greenwich, of one hour each, Nigeria falling into the zone with a
+# standard of one hour fast on Greenwich Mean Time.  Nigeria standard time is
+# now 30 minutes in advance of Greenwich Mean Time ... according to the new
+# proposal, standard time will be advanced another 30 minutes".  It was further
+# proposed that the firing of the time guns likewise be adjusted by 30 minutes
+# to compensate.
+# From Tim Parenti (2020-12-10), per P Chan (2020-12-11):
+# The text of Ordinance 18 of 1919, published in Nigeria Gazette, Vol 6, No 52,
+# shows that the change was assented to the following day and took effect "on
+# the 1st day of September, 1919."
+# Nigeria Gazette and Supplements 1919 Jan-Dec, Reference: 73266B-40,
+# img 245-246
+# https://microform.digital/boa/collections/77/volumes/539/nigeria-lagos-1887-1919
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone	Africa/Lagos	0:13:36 -	LMT	1919 Sep
+Zone	Africa/Lagos	0:13:35 -	LMT	1905 Jul  1
+			0:00	-	GMT	1908 Jul  1
+			0:13:35	-	LMT	1914 Jan  1
+			0:30	-	+0030	1919 Sep  1
 			1:00	-	WAT
 Link Africa/Lagos Africa/Bangui	     # Central African Republic
 Link Africa/Lagos Africa/Brazzaville # Rep. of the Congo
@@ -1298,8 +1453,21 @@ Zone	Africa/Sao_Tome	 0:26:56 -	LMT	1884
 # See Africa/Abidjan.
 
 # Seychelles
+
+# From P Chan (2020-11-27):
+# Standard Time was adopted on 1907-01-01.
+#
+# Standard Time Ordinance (Chapter 237)
+# The Laws of Seychelles in Force on the 31st December, 1971, Vol. 6, p 571
+# https://books.google.com/books?id=efE-AQAAIAAJ&pg=PA571
+#
+# From Tim Parenti (2020-12-05):
+# A footnote on https://books.google.com/books?id=DYdDAQAAMAAJ&pg=PA1689
+# confirms that Ordinance No. 9 of 1906 "was brought into force on the 1st
+# January, 1907."
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone	Indian/Mahe	3:41:48 -	LMT	1906 Jun # Victoria
+Zone	Indian/Mahe	3:41:48 -	LMT	1907 Jan  1 # Victoria
 			4:00	-	+04
 # From Paul Eggert (2001-05-30):
 # Aldabra, Farquhar, and Desroches, originally dependencies of the
diff --git a/asia b/asia
index 3ebfcb4..ed94413 100644
--- a/asia
+++ b/asia
@@ -1723,40 +1723,180 @@ Zone	Asia/Baghdad	2:57:40	-	LMT	1890
 # high on my favorite-country list (and not only because my wife's
 # family is from India).
 
-# From Shanks & Pottenger:
+# From P Chan (2020-10-27), with corrections:
+#
+# 1940-1946 Supplement No. 2 to the Palestine Gazette
+# # issue page  Order No.   dated      start        end         note
+# 1 1010  729  67 of 1940 1940-05-22 1940-05-31* 1940-09-30* revoked by #2
+# 2 1013  758  73 of 1940 1940-05-31 1940-05-31  1940-09-30
+# 3 1055 1574 196 of 1940 1940-11-06 1940-11-16  1940-12-31
+# 4 1066 1811 208 of 1940 1940-12-17 1940-12-31  1941-12-31
+# 5 1156 1967 116 of 1941 1941-12-16 1941-12-31  1942-12-31* amended by #6
+# 6 1228 1608  86 of 1942 1942-10-14 1941-12-31  1942-10-31
+# 7 1256  279  21 of 1943 1943-03-18 1943-03-31  1943-10-31
+# 8 1323  249  19 of 1944 1944-03-13 1944-03-31  1944-10-31
+# 9 1402  328  20 of 1945 1945-04-05 1945-04-15  1945-10-31
+#10 1487  596  14 of 1946 1946-04-04 1946-04-15  1946-10-31
+#
+# 1948 Iton Rishmi (Official Gazette of the Provisional Government)
+# #    issue    page   dated      start       end
+#11 2             7 1948-05-20 1948-05-22 1948-10-31*
+#	^This moved timezone to +04, replaced by #12 from 1948-08-31 24:00 GMT.
+#12 17 (Annex B) 84 1948-08-22 1948-08-31 1948-10-31
+#
+# 1949-2000 Kovetz HaTakanot (Collection of Regulations)
+# # issue page  dated      start       end            note
+#13    6  133 1949-03-23 1949-04-30  1949-10-31
+#14   80  755 1950-03-17 1950-04-15  1950-09-14
+#15  164  782 1951-03-22 1951-03-31  1951-09-29* amended by #16
+#16  206 1940 1951-09-23 ----------  1951-10-22* amended by #17
+#17  212   78 1951-10-19 ----------  1951-11-10
+#18  254  652 1952-03-03 1952-04-19  1952-09-27* amended by #19
+#19  300   11 1952-09-15 ----------  1952-10-18
+#20  348  817 1953-03-03 1953-04-11  1953-09-12
+#21  420  385 1954-02-17 1954-06-12  1954-09-11
+#22  497  548 1955-01-14 1955-06-11  1955-09-10
+#23  591  608 1956-03-12 1956-06-02  1956-09-29
+#24  680  957 1957-02-08 1957-04-27  1957-09-21
+#25 3192 1418 1974-06-28 1974-07-06  1974-10-12
+#26 3322 1389 1975-04-03 1975-04-19  1975-08-30
+#27 4146 2089 1980-07-15 1980-08-02  1980-09-13
+#28 4604 1081 1984-02-22 1984-05-05* 1984-08-25* revoked by #29
+#29 4619 1312 1984-04-06 1984-05-05  1984-08-25
+#30 4744  475 1984-12-23 1985-04-13  1985-09-14* amended by #31
+#31 4851 1848 1985-08-18 ----------  1985-08-31
+#32 4932  899 1986-04-22 1986-05-17  1986-09-06
+#33 5013  580 1987-02-15 1987-04-18* 1987-08-22* revoked by #34
+#34 5021  744 1987-03-30 1987-04-14  1987-09-12
+#35 5096  659 1988-02-14 1988-04-09  1988-09-03
+#36 5167  514 1989-02-03 1989-04-29  1989-09-02
+#37 5248  375 1990-01-23 1990-03-24  1990-08-25
+#38 5335  612 1991-02-10 1991-03-09* 1991-08-31	 amended by #39
+#			 1992-03-28  1992-09-05
+#39 5339  709 1991-03-04 1991-03-23  ----------
+#40 5506  503 1993-02-18 1993-04-02  1993-09-05
+#			 1994-04-01  1994-08-28
+#			 1995-03-31  1995-09-03
+#41 5731  438 1996-01-01 1996-03-14  1996-09-15
+#			 1997-03-13* 1997-09-18* overridden by 1997 Temp Prov
+#			 1998-03-19* 1998-09-17* revoked by #42
+#42 5853 1243 1997-09-18 1998-03-19  1998-09-05
+#43 5937   77 1998-10-18 1999-04-02  1999-09-03
+#			 2000-04-14* 2000-09-15* revoked by #44
+#			 2001-04-13* 2001-09-14* revoked by #44
+#44 6024   39 2000-03-14 2000-04-14  2000-10-22* overridden by 2000 Temp Prov
+#			 2001-04-06* 2001-10-10* overridden by 2000 Temp Prov
+#			 2002-03-29* 2002-10-29* overridden by 2000 Temp Prov
+#
+# These are laws enacted by the Knesset since the Minister could only alter the
+# transition dates at least six months in advanced under the 1992 Law.
+#				dated		start		end
+# 1997 Temporary Provisions	1997-03-06	1997-03-20	1997-09-13
+# 2000 Temporary Provisions	2000-07-28	----------	2000-10-06
+#						2001-04-09	2001-09-24
+#						2002-03-29	2002-10-07
+#						2003-03-28	2003-10-03
+#						2004-04-07	2004-09-22
+# Note:
+# Transition times in 1940-1957 (#1-#24) were midnight GMT,
+# in 1974-1998 (#25-#42 and the 1997 Temporary Provisions) were midnight,
+# in 1999-April 2000 (#43,#44) were 02:00,
+# in the 2000 Temporary Provisions were 01:00.
+#
+# -----------------------------------------------------------------------------
+# Links:
+# 1 https://findit.library.yale.edu/images_layout/view?parentoid=15537490&increment=687
+# 2 https://findit.library.yale.edu/images_layout/view?parentoid=15537490&increment=716
+# 3 https://findit.library.yale.edu/images_layout/view?parentoid=15537491&increment=721
+# 4 https://findit.library.yale.edu/images_layout/view?parentoid=15537491&increment=958
+# 5 https://findit.library.yale.edu/images_layout/view?parentoid=15537502&increment=558
+# 6 https://findit.library.yale.edu/images_layout/view?parentoid=15537511&increment=105
+# 7 https://findit.library.yale.edu/images_layout/view?parentoid=15537516&increment=278
+# 8 https://findit.library.yale.edu/images_layout/view?parentoid=15537522&increment=248
+# 9 https://findit.library.yale.edu/images_layout/view?parentoid=15537530&increment=329
+#10 https://findit.library.yale.edu/images_layout/view?parentoid=15537537&increment=601
+#11 https://www.nevo.co.il/law_word/law12/er-002.pdf#page=3
+#12 https://www.nevo.co.il/law_word/law12/er-017-t2.pdf#page=4
+#13 https://www.nevo.co.il/law_word/law06/tak-0006.pdf#page=3
+#14 https://www.nevo.co.il/law_word/law06/tak-0080.pdf#page=7
+#15 https://www.nevo.co.il/law_word/law06/tak-0164.pdf#page=10
+#16 https://www.nevo.co.il/law_word/law06/tak-0206.pdf#page=4
+#17 https://www.nevo.co.il/law_word/law06/tak-0212.pdf#page=2
+#18 https://www.nevo.co.il/law_word/law06/tak-0254.pdf#page=4
+#19 https://www.nevo.co.il/law_word/law06/tak-0300.pdf#page=5
+#20 https://www.nevo.co.il/law_word/law06/tak-0348.pdf#page=3
+#21 https://www.nevo.co.il/law_word/law06/tak-0420.pdf#page=5
+#22 https://www.nevo.co.il/law_word/law06/tak-0497.pdf#page=10
+#23 https://www.nevo.co.il/law_word/law06/tak-0591.pdf#page=6
+#24 https://www.nevo.co.il/law_word/law06/tak-0680.pdf#page=3
+#25 https://www.nevo.co.il/law_word/law06/tak-3192.pdf#page=2
+#26 https://www.nevo.co.il/law_word/law06/tak-3322.pdf#page=5
+#27 https://www.nevo.co.il/law_word/law06/tak-4146.pdf#page=2
+#28 https://www.nevo.co.il/law_word/law06/tak-4604.pdf#page=7
+#29 https://www.nevo.co.il/law_word/law06/tak-4619.pdf#page=2
+#30 https://www.nevo.co.il/law_word/law06/tak-4744.pdf#page=11
+#31 https://www.nevo.co.il/law_word/law06/tak-4851.pdf#page=2
+#32 https://www.nevo.co.il/law_word/law06/tak-4932.pdf#page=19
+#33 https://www.nevo.co.il/law_word/law06/tak-5013.pdf#page=8
+#34 https://www.nevo.co.il/law_word/law06/tak-5021.pdf#page=8
+#35 https://www.nevo.co.il/law_word/law06/tak-5096.pdf#page=3
+#36 https://www.nevo.co.il/law_word/law06/tak-5167.pdf#page=2
+#37 https://www.nevo.co.il/law_word/law06/tak-5248.pdf#page=7
+#38 https://www.nevo.co.il/law_word/law06/tak-5335.pdf#page=6
+#39 https://www.nevo.co.il/law_word/law06/tak-5339.pdf#page=7
+#40 https://www.nevo.co.il/law_word/law06/tak-5506.pdf#page=19
+#41 https://www.nevo.co.il/law_word/law06/tak-5731.pdf#page=2
+#42 https://www.nevo.co.il/law_word/law06/tak-5853.pdf#page=3
+#43 https://www.nevo.co.il/law_word/law06/tak-5937.pdf#page=9
+#44 https://www.nevo.co.il/law_word/law06/tak-6024.pdf#page=4
+#
+# Time Determination (Temporary Provisions) Law, 1997
+# https://www.nevo.co.il/law_html/law19/p201_003.htm
+#
+# Time Determination (Temporary Provisions) Law, 2000
+# https://www.nevo.co.il/law_html/law19/p201_004.htm
+#
+# Time Determination Law, 1992 and amendments
+# https://www.nevo.co.il/law_html/law01/p201_002.htm
+# https://main.knesset.gov.il/Activity/Legislation/Laws/Pages/LawPrimary.aspx?lawitemid=2001174
+
+# From Paul Eggert (2020-10-27):
+# Several of the midnight transitions mentioned above are ambiguous;
+# are they 00:00, 00:00s, 24:00, or 24:00s?  When resolving these ambiguities,
+# try to minimize changes from previous tzdb versions, for lack of better info.
+# Commentary from previous versions is included below, to help explain this.
+
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Zion	1940	only	-	Jun	 1	0:00	1:00	D
-Rule	Zion	1942	1944	-	Nov	 1	0:00	0	S
-Rule	Zion	1943	only	-	Apr	 1	2:00	1:00	D
-Rule	Zion	1944	only	-	Apr	 1	0:00	1:00	D
-Rule	Zion	1945	only	-	Apr	16	0:00	1:00	D
-Rule	Zion	1945	only	-	Nov	 1	2:00	0	S
-Rule	Zion	1946	only	-	Apr	16	2:00	1:00	D
-Rule	Zion	1946	only	-	Nov	 1	0:00	0	S
-Rule	Zion	1948	only	-	May	23	0:00	2:00	DD
-Rule	Zion	1948	only	-	Sep	 1	0:00	1:00	D
-Rule	Zion	1948	1949	-	Nov	 1	2:00	0	S
-Rule	Zion	1949	only	-	May	 1	0:00	1:00	D
-Rule	Zion	1950	only	-	Apr	16	0:00	1:00	D
-Rule	Zion	1950	only	-	Sep	15	3:00	0	S
-Rule	Zion	1951	only	-	Apr	 1	0:00	1:00	D
-Rule	Zion	1951	only	-	Nov	11	3:00	0	S
-Rule	Zion	1952	only	-	Apr	20	2:00	1:00	D
-Rule	Zion	1952	only	-	Oct	19	3:00	0	S
-Rule	Zion	1953	only	-	Apr	12	2:00	1:00	D
-Rule	Zion	1953	only	-	Sep	13	3:00	0	S
-Rule	Zion	1954	only	-	Jun	13	0:00	1:00	D
-Rule	Zion	1954	only	-	Sep	12	0:00	0	S
-Rule	Zion	1955	only	-	Jun	11	2:00	1:00	D
-Rule	Zion	1955	only	-	Sep	11	0:00	0	S
-Rule	Zion	1956	only	-	Jun	 3	0:00	1:00	D
-Rule	Zion	1956	only	-	Sep	30	3:00	0	S
-Rule	Zion	1957	only	-	Apr	29	2:00	1:00	D
-Rule	Zion	1957	only	-	Sep	22	0:00	0	S
-Rule	Zion	1974	only	-	Jul	 7	0:00	1:00	D
-Rule	Zion	1974	only	-	Oct	13	0:00	0	S
-Rule	Zion	1975	only	-	Apr	20	0:00	1:00	D
-Rule	Zion	1975	only	-	Aug	31	0:00	0	S
+Rule	Zion	1940	only	-	May	31	24:00u	1:00	D
+Rule	Zion	1940	only	-	Sep	30	24:00u	0	S
+Rule	Zion	1940	only	-	Nov	16	24:00u	1:00	D
+Rule	Zion	1942	1946	-	Oct	31	24:00u	0	S
+Rule	Zion	1943	1944	-	Mar	31	24:00u	1:00	D
+Rule	Zion	1945	1946	-	Apr	15	24:00u	1:00	D
+Rule	Zion	1948	only	-	May	22	24:00u	2:00	DD
+Rule	Zion	1948	only	-	Aug	31	24:00u	1:00	D
+Rule	Zion	1948	1949	-	Oct	31	24:00u	0	S
+Rule	Zion	1949	only	-	Apr	30	24:00u	1:00	D
+Rule	Zion	1950	only	-	Apr	15	24:00u	1:00	D
+Rule	Zion	1950	only	-	Sep	14	24:00u	0	S
+Rule	Zion	1951	only	-	Mar	31	24:00u	1:00	D
+Rule	Zion	1951	only	-	Nov	10	24:00u	0	S
+Rule	Zion	1952	only	-	Apr	19	24:00u	1:00	D
+Rule	Zion	1952	only	-	Oct	18	24:00u	0	S
+Rule	Zion	1953	only	-	Apr	11	24:00u	1:00	D
+Rule	Zion	1953	only	-	Sep	12	24:00u	0	S
+Rule	Zion	1954	only	-	Jun	12	24:00u	1:00	D
+Rule	Zion	1954	only	-	Sep	11	24:00u	0	S
+Rule	Zion	1955	only	-	Jun	11	24:00u	1:00	D
+Rule	Zion	1955	only	-	Sep	10	24:00u	0	S
+Rule	Zion	1956	only	-	Jun	 2	24:00u	1:00	D
+Rule	Zion	1956	only	-	Sep	29	24:00u	0	S
+Rule	Zion	1957	only	-	Apr	27	24:00u	1:00	D
+Rule	Zion	1957	only	-	Sep	21	24:00u	0	S
+Rule	Zion	1974	only	-	Jul	 6	24:00	1:00	D
+Rule	Zion	1974	only	-	Oct	12	24:00	0	S
+Rule	Zion	1975	only	-	Apr	19	24:00	1:00	D
+Rule	Zion	1975	only	-	Aug	30	24:00	0	S
 
 # From Alois Treindl (2019-03-06):
 # http://www.moin.gov.il/Documents/שעון%20קיץ/clock-50-years-7-2014.pdf
@@ -1769,25 +1909,24 @@ Rule	Zion	1975	only	-	Aug	31	0:00	0	S
 # From Paul Eggert (2019-03-06):
 # Also see this thread about the moin.gov.il URL:
 # https://mm.icann.org/pipermail/tz/2018-November/027194.html
-Rule	Zion	1980	only	-	Aug	 2	0:00	1:00	D
-Rule	Zion	1980	only	-	Sep	13	1:00	0	S
-Rule	Zion	1984	only	-	May	 5	0:00	1:00	D
-Rule	Zion	1984	only	-	Aug	25	1:00	0	S
-
-# From Shanks & Pottenger:
-Rule	Zion	1985	only	-	Apr	14	0:00	1:00	D
-Rule	Zion	1985	only	-	Sep	15	0:00	0	S
-Rule	Zion	1986	only	-	May	18	0:00	1:00	D
-Rule	Zion	1986	only	-	Sep	 7	0:00	0	S
-Rule	Zion	1987	only	-	Apr	15	0:00	1:00	D
-Rule	Zion	1987	only	-	Sep	13	0:00	0	S
+Rule	Zion	1980	only	-	Aug	 2	24:00s	1:00	D
+Rule	Zion	1980	only	-	Sep	13	24:00s	0	S
+Rule	Zion	1984	only	-	May	 5	24:00s	1:00	D
+Rule	Zion	1984	only	-	Aug	25	24:00s	0	S
+
+Rule	Zion	1985	only	-	Apr	13	24:00	1:00	D
+Rule	Zion	1985	only	-	Aug	31	24:00	0	S
+Rule	Zion	1986	only	-	May	17	24:00	1:00	D
+Rule	Zion	1986	only	-	Sep	 6	24:00	0	S
+Rule	Zion	1987	only	-	Apr	14	24:00	1:00	D
+Rule	Zion	1987	only	-	Sep	12	24:00	0	S
 
 # From Avigdor Finkelstein (2014-03-05):
 # I check the Parliament (Knesset) records and there it's stated that the
 # [1988] transition should take place on Saturday night, when the Sabbath
 # ends and changes to Sunday.
-Rule	Zion	1988	only	-	Apr	10	0:00	1:00	D
-Rule	Zion	1988	only	-	Sep	 4	0:00	0	S
+Rule	Zion	1988	only	-	Apr	 9	24:00	1:00	D
+Rule	Zion	1988	only	-	Sep	 3	24:00	0	S
 
 # From Ephraim Silverberg
 # (1997-03-04, 1998-03-16, 1998-12-28, 2000-01-17, 2000-07-25, 2004-12-22,
@@ -1817,14 +1956,14 @@ Rule	Zion	1988	only	-	Sep	 4	0:00	0	S
 # (the eve of the 7th of Tishrei in the lunar Hebrew calendar).
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Zion	1989	only	-	Apr	30	0:00	1:00	D
-Rule	Zion	1989	only	-	Sep	 3	0:00	0	S
-Rule	Zion	1990	only	-	Mar	25	0:00	1:00	D
-Rule	Zion	1990	only	-	Aug	26	0:00	0	S
-Rule	Zion	1991	only	-	Mar	24	0:00	1:00	D
-Rule	Zion	1991	only	-	Sep	 1	0:00	0	S
-Rule	Zion	1992	only	-	Mar	29	0:00	1:00	D
-Rule	Zion	1992	only	-	Sep	 6	0:00	0	S
+Rule	Zion	1989	only	-	Apr	29	24:00	1:00	D
+Rule	Zion	1989	only	-	Sep	 2	24:00	0	S
+Rule	Zion	1990	only	-	Mar	24	24:00	1:00	D
+Rule	Zion	1990	only	-	Aug	25	24:00	0	S
+Rule	Zion	1991	only	-	Mar	23	24:00	1:00	D
+Rule	Zion	1991	only	-	Aug	31	24:00	0	S
+Rule	Zion	1992	only	-	Mar	28	24:00	1:00	D
+Rule	Zion	1992	only	-	Sep	 5	24:00	0	S
 Rule	Zion	1993	only	-	Apr	 2	0:00	1:00	D
 Rule	Zion	1993	only	-	Sep	 5	0:00	0	S
 
@@ -1853,10 +1992,10 @@ Rule	Zion	1995	only	-	Sep	 3	0:00	0	S
 #       where YYYY is the relevant year.
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Zion	1996	only	-	Mar	15	0:00	1:00	D
-Rule	Zion	1996	only	-	Sep	16	0:00	0	S
-Rule	Zion	1997	only	-	Mar	21	0:00	1:00	D
-Rule	Zion	1997	only	-	Sep	14	0:00	0	S
+Rule	Zion	1996	only	-	Mar	14	24:00	1:00	D
+Rule	Zion	1996	only	-	Sep	15	24:00	0	S
+Rule	Zion	1997	only	-	Mar	20	24:00	1:00	D
+Rule	Zion	1997	only	-	Sep	13	24:00	0	S
 Rule	Zion	1998	only	-	Mar	20	0:00	1:00	D
 Rule	Zion	1998	only	-	Sep	 6	0:00	0	S
 Rule	Zion	1999	only	-	Apr	 2	2:00	1:00	D
@@ -1908,14 +2047,15 @@ Rule	Zion	2010	only	-	Sep	12	2:00	0	S
 Rule	Zion	2011	only	-	Oct	 2	2:00	0	S
 Rule	Zion	2012	only	-	Sep	23	2:00	0	S
 
-# From Ephraim Silverberg (2013-06-27):
-# On June 23, 2013, the Israeli government approved changes to the
-# Time Decree Law.  The next day, the changes passed the First Reading
-# in the Knesset.  The law is expected to pass the Second and Third
-# (final) Readings by the beginning of September 2013.
-#
-# As of 2013, DST starts at 02:00 on the Friday before the last Sunday
-# in March.  DST ends at 02:00 on the last Sunday of October.
+# From Ephraim Silverberg (2020-10-26):
+# The current time law (2013) from the State of Israel can be viewed
+# (in Hebrew) at:
+# ftp://ftp.cs.huji.ac.il/pub/tz/israel/announcements/2013+law.pdf
+# It translates to:
+# Every year, in the period from the Friday before the last Sunday in
+# the month of March at 02:00 a.m. until the last Sunday of the month
+# of October at 02:00 a.m., Israel Time will be advanced an additional
+# hour such that it will be UTC+3.
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
 Rule	Zion	2013	max	-	Mar	Fri>=23	2:00	1:00	D
diff --git a/australasia b/australasia
index aa7ab7f..cf8a063 100644
--- a/australasia
+++ b/australasia
@@ -14,16 +14,13 @@
 # Please see the notes below for the controversy about "EST" versus "AEST" etc.
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Aus	1917	only	-	Jan	 1	0:01	1:00	D
-Rule	Aus	1917	only	-	Mar	25	2:00	0	S
-Rule	Aus	1942	only	-	Jan	 1	2:00	1:00	D
-Rule	Aus	1942	only	-	Mar	29	2:00	0	S
-Rule	Aus	1942	only	-	Sep	27	2:00	1:00	D
-Rule	Aus	1943	1944	-	Mar	lastSun	2:00	0	S
-Rule	Aus	1943	only	-	Oct	 3	2:00	1:00	D
-# Go with Whitman and the Australian National Standards Commission, which
-# says W Australia didn't use DST in 1943/1944.  Ignore Whitman's claim that
-# 1944/1945 was just like 1943/1944.
+Rule	Aus	1917	only	-	Jan	 1	2:00s	1:00	D
+Rule	Aus	1917	only	-	Mar	lastSun	2:00s	0	S
+Rule	Aus	1942	only	-	Jan	 1	2:00s	1:00	D
+Rule	Aus	1942	only	-	Mar	lastSun	2:00s	0	S
+Rule	Aus	1942	only	-	Sep	27	2:00s	1:00	D
+Rule	Aus	1943	1944	-	Mar	lastSun	2:00s	0	S
+Rule	Aus	1943	only	-	Oct	 3	2:00s	1:00	D
 
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 # Northern Territory
@@ -115,8 +112,12 @@ Zone Australia/Adelaide	9:14:20 -	LMT	1895 Feb
 # says King Island didn't observe DST from WWII until late 1971.
 #
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
+Rule	AT	1916	only	-	Oct	Sun>=1	2:00s	1:00	D
+Rule	AT	1917	only	-	Mar	lastSun	2:00s	0	S
+Rule	AT	1917	1918	-	Oct	Sun>=22	2:00s	1:00	D
+Rule	AT	1918	1919	-	Mar	Sun>=1	2:00s	0	S
 Rule	AT	1967	only	-	Oct	Sun>=1	2:00s	1:00	D
-Rule	AT	1968	only	-	Mar	lastSun	2:00s	0	S
+Rule	AT	1968	only	-	Mar	Sun>=29	2:00s	0	S
 Rule	AT	1968	1985	-	Oct	lastSun	2:00s	1:00	D
 Rule	AT	1969	1971	-	Mar	Sun>=8	2:00s	0	S
 Rule	AT	1972	only	-	Feb	lastSun	2:00s	0	S
@@ -136,15 +137,9 @@ Rule	AT	2007	only	-	Mar	lastSun	2:00s	0	S
 Rule	AT	2008	max	-	Apr	Sun>=1	2:00s	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone Australia/Hobart	9:49:16	-	LMT	1895 Sep
-			10:00	-	AEST	1916 Oct  1  2:00
-			10:00	1:00	AEDT	1917 Feb
+			10:00	AT	AE%sT	1919 Oct 24
 			10:00	Aus	AE%sT	1967
 			10:00	AT	AE%sT
-Zone Australia/Currie	9:35:28	-	LMT	1895 Sep
-			10:00	-	AEST	1916 Oct  1  2:00
-			10:00	1:00	AEDT	1917 Feb
-			10:00	Aus	AE%sT	1971 Jul
-			10:00	AT	AE%sT
 
 # Victoria
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
@@ -873,13 +868,36 @@ Zone	Pacific/Wake	11:06:28 -	LMT	1901
 
 
 # Vanuatu
+
+# From P Chan (2020-11-27):
+# Joint Daylight Saving Regulation No 59 of 1973
+# New Hebrides Condominium Gazette No 336. December 1973
+# http://www.paclii.org/vu/other/VUNHGovGaz//1973/11.pdf#page=15
+#
+# Joint Daylight Saving (Repeal) Regulation No 10 of 1974
+# New Hebrides Condominium Gazette No 336. March 1974
+# http://www.paclii.org/vu/other/VUNHGovGaz//1974/3.pdf#page=11
+#
+# Summer Time Act No. 35 of 1982 [commenced 1983-09-01]
+# http://www.paclii.org/vu/other/VUGovGaz/1982/32.pdf#page=48
+#
+# Summer Time Act (Cap 157)
+# Laws of the Republic of Vanuatu Revised Edition 1988
+# http://www.paclii.org/cgi-bin/sinodisp/vu/legis/consol_act1988/sta147/sta147.html
+#
+# Summer Time (Amendment) Act No. 6 of 1991 [commenced 1991-11-11]
+# http://www.paclii.org/vu/legis/num_act/sta1991227/
+#
+# Summer Time (Repeal) Act No. 4 of 1993 [commenced 1993-05-03]
+# http://www.paclii.org/vu/other/VUGovGaz/1993/15.pdf#page=59
+
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Vanuatu	1983	only	-	Sep	25	0:00	1:00	-
-Rule	Vanuatu	1984	1991	-	Mar	Sun>=23	0:00	0	-
-Rule	Vanuatu	1984	only	-	Oct	23	0:00	1:00	-
-Rule	Vanuatu	1985	1991	-	Sep	Sun>=23	0:00	1:00	-
-Rule	Vanuatu	1992	1993	-	Jan	Sun>=23	0:00	0	-
-Rule	Vanuatu	1992	only	-	Oct	Sun>=23	0:00	1:00	-
+Rule	Vanuatu	1973	only	-	Dec	22	12:00u	1:00	-
+Rule	Vanuatu	1974	only	-	Mar	30	12:00u	0	-
+Rule	Vanuatu	1983	1991	-	Sep	Sat>=22	24:00	1:00	-
+Rule	Vanuatu	1984	1991	-	Mar	Sat>=22	24:00	0	-
+Rule	Vanuatu	1992	1993	-	Jan	Sat>=22	24:00	0	-
+Rule	Vanuatu	1992	only	-	Oct	Sat>=22	24:00	1:00	-
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone	Pacific/Efate	11:13:16 -	LMT	1912 Jan 13 # Vila
 			11:00	Vanuatu	+11/+12
@@ -958,6 +976,25 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 # Electronic Journal of Australian and New Zealand History (1997-03-03)
 # http://www.jcu.edu.au/aff/history/reviews/davison.htm
 
+# From P Chan (2020-11-20):
+# Daylight Saving Act 1916 (No. 40 of 1916) [1916-12-21, commenced 1917-01-01]
+# http://classic.austlii.edu.au/au/legis/cth/num_act/dsa1916401916192/
+#
+# Daylight Saving Repeal Act 1917 (No. 35 of 1917) [1917-09-25]
+# http://classic.austlii.edu.au/au/legis/cth/num_act/dsra1917351917243/
+#
+# Statutory Rules 1941, No. 323 [1941-12-24]
+# https://www.legislation.gov.au/Details/C1941L00323
+#
+# Statutory Rules 1942, No. 392 [1942-09-10]
+# https://www.legislation.gov.au/Details/C1942L00392
+#
+# Statutory Rules 1943, No. 241 [1943-09-29]
+# https://www.legislation.gov.au/Details/C1943L00241
+#
+# All transition times should be 02:00 standard time.
+
+
 # From Paul Eggert (2005-12-08):
 # Implementation Dates of Daylight Saving Time within Australia
 # http://www.bom.gov.au/climate/averages/tables/dst_times.shtml
@@ -1350,6 +1387,27 @@ Zone	Pacific/Wallis	12:15:20 -	LMT	1901
 
 # Tasmania
 
+# From P Chan (2020-11-20):
+# Tasmania observed DST in 1916-1919.
+#
+# Daylight Saving Act, 1916 (7 Geo V, No 2) [1916-09-22]
+# http://classic.austlii.edu.au/au/legis/tas/num_act/tdsa19167gvn2267/
+#
+# Daylight Saving Amendment Act, 1917 (8 Geo V, No 5) [1917-10-01]
+# http://classic.austlii.edu.au/au/legis/tas/num_act/tdsaa19178gvn5347/
+#
+# Daylight Saving Act Repeal Act, 1919 (10 Geo V, No 9) [1919-10-24]
+# http://classic.austlii.edu.au/au/legis/tas/num_act/tdsara191910gvn9339/
+#
+# King Island is mentioned in the 1967 Act but not the 1968 Act.
+# Therefore it possibly observed DST from 1968/69.
+#
+# Daylight Saving Act 1967 (No. 33 of 1967) [1967-09-22]
+# http://classic.austlii.edu.au/au/legis/tas/num_act/dsa196733o1967211/
+#
+# Daylight Saving Act 1968 (No. 42 of 1968) [1968-10-15]
+# http://classic.austlii.edu.au/au/legis/tas/num_act/dsa196842o1968211/
+
 # The rules for 1967 through 1991 were reported by George Shepherd
 # via Simon Woodhead via Robert Elz (1991-03-06):
 # #  The state of TASMANIA.. [Courtesy Tasmanian Dept of Premier + Cabinet ]
diff --git a/backward b/backward
index e13ae52..0c55be2 100644
--- a/backward
+++ b/backward
@@ -49,6 +49,7 @@ Link	Atlantic/Faroe		Atlantic/Faeroe
 Link	Europe/Oslo		Atlantic/Jan_Mayen
 Link	Australia/Sydney	Australia/ACT
 Link	Australia/Sydney	Australia/Canberra
+Link	Australia/Hobart	Australia/Currie
 Link	Australia/Lord_Howe	Australia/LHI
 Link	Australia/Sydney	Australia/NSW
 Link	Australia/Darwin	Australia/North
diff --git a/backzone b/backzone
index 563aff6..3ce7277 100644
--- a/backzone
+++ b/backzone
@@ -623,6 +623,12 @@ Zone Atlantic/St_Helena	-0:22:48 -	LMT	1890 # Jamestown
 			-0:22:48 -	JMT	1951 # Jamestown Mean Time
 			 0:00	-	GMT
 
+# King Island
+Zone Australia/Currie	9:35:28	-	LMT	1895 Sep
+			10:00	AT	AE%sT	1919 Oct 24
+			10:00	Aus	AE%sT	1968 Oct 15
+			10:00	AT	AE%sT
+
 # Northern Ireland
 Zone	Europe/Belfast	-0:23:40 -	LMT	1880 Aug  2
 			-0:25:21 -	DMT	1916 May 21  2:00
diff --git a/etcetera b/etcetera
index a1606bd..1dc7411 100644
--- a/etcetera
+++ b/etcetera
@@ -3,12 +3,11 @@
 # This file is in the public domain, so clarified as of
 # 2009-05-17 by Arthur David Olson.
 
-# These entries are mostly present for historical reasons, so that
-# people in areas not otherwise covered by the tz files could "zic -l"
-# to a timezone that was right for their area.  These days, the
-# tz files cover almost all the inhabited world, and the only practical
-# need now for the entries that are not on UTC are for ships at sea
-# that cannot use POSIX TZ settings.
+# These entries are for uses not otherwise covered by the tz database.
+# Their main practical use is for platforms like Android that lack
+# support for POSIX-style TZ strings.  On such platforms these entries
+# can be useful if the timezone database is wrong or if a ship or
+# aircraft at sea is not in a timezone.
 
 # Starting with POSIX 1003.1-2001, the entries below are all
 # unnecessary as settings for the TZ environment variable.  E.g.,
diff --git a/europe b/europe
index ea23736..bba4d56 100644
--- a/europe
+++ b/europe
@@ -2892,6 +2892,19 @@ Zone Europe/Astrakhan	 3:12:12 -	LMT	1924 May
 # The law has been published today on
 # http://publication.pravo.gov.ru/Document/View/0001201810110037
 
+# From Alexander Krivenyshev (2020-11-27):
+# The State Duma approved (Nov 24, 2020) the transition of the Volgograd
+# region to the Moscow time zone....
+# https://sozd.duma.gov.ru/bill/1012130-7
+#
+# From Stepan Golosunov (2020-12-05):
+# Currently proposed text for the second reading (expected on December 8) ...
+# changes the date to December 27. https://v1.ru/text/gorod/2020/12/04/69601031/
+#
+# From Stepan Golosunov (2020-12-22):
+# The law was published today on
+# http://publication.pravo.gov.ru/Document/View/0001202012220002
+
 Zone Europe/Volgograd	 2:57:40 -	LMT	1920 Jan  3
 			 3:00	-	+03	1930 Jun 21
 			 4:00	-	+04	1961 Nov 11
@@ -2901,7 +2914,8 @@ Zone Europe/Volgograd	 2:57:40 -	LMT	1920 Jan  3
 			 3:00	Russia	+03/+04	2011 Mar 27  2:00s
 			 4:00	-	+04	2014 Oct 26  2:00s
 			 3:00	-	+03	2018 Oct 28  2:00s
-			 4:00	-	+04
+			 4:00	-	+04	2020 Dec 27  2:00s
+			 3:00	-	+03
 
 # From Paul Eggert (2016-11-11):
 # Europe/Saratov covers:
diff --git a/leapseconds.awk b/leapseconds.awk
index 1d3c606..b6c48bc 100755
--- a/leapseconds.awk
+++ b/leapseconds.awk
@@ -24,6 +24,10 @@ BEGIN {
   print "# NIST format leap-seconds.list file, which can be copied from"
   print "# <ftp://ftp.nist.gov/pub/time/leap-seconds.list>"
   print "# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>."
+  print "# The NIST file is used instead of its IERS upstream counterpart"
+  print "# <https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list>"
+  print "# because under US law the NIST file is public domain"
+  print "# whereas the IERS file's copyright and license status is unclear."
   print "# For more about leap-seconds.list, please see"
   print "# The NTP Timescale and Leap Seconds"
   print "# <https://www.eecis.udel.edu/~mills/leap.html>."
diff --git a/northamerica b/northamerica
index 675c648..ddc5759 100644
--- a/northamerica
+++ b/northamerica
@@ -2234,7 +2234,7 @@ Zone America/Creston	-7:46:04 -	LMT	1884
 #     to say eight hours behind Greenwich Time.
 #
 # * O.I.C. 1980/02 INTERPRETATION ACT
-#   [no online source found]
+#   https://mm.icann.org/pipermail/tz/attachments/20201125/d5adc93b/CAYTOIC1980-02DST1980-01-04-0001.pdf
 #
 # * Yukon Daylight Saving Time, YOIC 1987/56
 #   https://www.canlii.org/en/yk/laws/regu/yoic-1987-56/latest/yoic-1987-56.html
@@ -2935,12 +2935,38 @@ Zone America/Tijuana	-7:48:04 -	LMT	1922 Jan  1  0:11:56
 #
 # For 1899 Milne gives -5:09:29.5; round that.
 #
+# From P Chan (2020-11-27, corrected on 2020-12-02):
+# There were two periods of DST observed in 1942-1945: 1942-05-01
+# midnight to 1944-12-31 midnight and 1945-02-01 to 1945-10-17 midnight.
+# "midnight" should mean 24:00 from the context.
+#
+# War Time Order 1942 [1942-05-01] and War Time (No. 2) Order 1942  [1942-09-29]
+# Appendix to the Statutes of 7 George VI. and the Year 1942. p 34, 43
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA3-PA34
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA3-PA43
+#
+# War Time Order 1943 [1943-03-31] and War Time Order 1944 [1943-12-29]
+# Appendix to the Statutes of 8 George VI. and the Year 1943. p 9-10, 28-29
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA4-PA9
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA4-PA28
+#
+# War Time Order 1945 [1945-01-31] and the Order which revoke War Time Order
+# 1945 [1945-10-16] Appendix to the Statutes of 9 George VI. and the Year
+# 1945. p 160, 247-248
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA6-PA160
+# https://books.google.com/books?id=5rlNAQAAIAAJ&pg=RA6-PA247
+#
 # From Sue Williams (2006-12-07):
 # The Bahamas announced about a month ago that they plan to change their DST
 # rules to sync with the U.S. starting in 2007....
 # http://www.jonesbahamas.com/?c=45&a=10412
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
+Rule	Bahamas	1942	only	-	May	 1	24:00	1:00	W
+Rule	Bahamas	1944	only	-	Dec	31	24:00	0	S
+Rule	Bahamas	1945	only	-	Feb	 1	0:00	1:00	W
+Rule	Bahamas	1945	only	-	Aug	14	23:00u	1:00	P # Peace
+Rule	Bahamas	1945	only	-	Oct	17	24:00	0	S
 Rule	Bahamas	1964	1975	-	Oct	lastSun	2:00	0	S
 Rule	Bahamas	1964	1975	-	Apr	lastSun	2:00	1:00	D
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
@@ -2964,34 +2990,161 @@ Zone America/Barbados	-3:58:29 -	LMT	1924 # Bridgetown
 			-4:00	Barb	A%sT
 
 # Belize
-# Whitman entirely disagrees with Shanks; go with Shanks & Pottenger.
+
+# From P Chan (2020-11-03):
+# Below are some laws related to the time in British Honduras/Belize:
+#
+# Definition of Time Ordinance, 1927 (No.4 of 1927) [1927-04-01]
+# Ordinances of British Honduras Passed in the Year 1927, p 19-20
+# https://books.google.com/books?id=LqEpAQAAMAAJ&pg=RA3-PA19
+#
+# Definition of Time (Amendment) Ordinance, 1942 (No. 5 of 1942) [1942-06-27]
+# Ordinances of British Honduras Passed in the Year 1942, p 31-32
+# https://books.google.com/books?id=h6MpAQAAMAAJ&pg=RA6-PA95-IA44
+#
+# Definition of Time Ordinance, 1945 (No. 19 of 1945) [1945-12-15]
+# Ordinances of British Honduras Passed in the Year 1945, p 49-50
+# https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA2-PP1
+#
+# Definition of Time Ordinance, 1947 (No. 1 of 1947) [1947-03-11]
+# Ordinances of British Honduras Passed in the Year 1947, p 1-2
+# https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA3-PA1
+#
+# Time (Definition of) Ordinance  (Chapter 180)
+# The Laws of British Honduras in Force on the 15th Day of September, 1958 , Volume IV, p 2580
+# https://books.google.com/books?id=v5QpAQAAMAAJ&pg=PA2580
+#
+# Time (Definition of) (Amendment) Ordinance, 1968 (No. 13 of 1968) [1968-08-03]
+# https://books.google.com/books?id=xij7KEB_58wC&pg=RA1-PA428-IA9
+#
+# Definition of Time Act (Chapter 339)
+# Law of Belize, Revised Edition 2000
+# http://www.belizelaw.org/web/lawadmin/PDF%20files/cap339.pdf
+
+# From Paul Eggert (2020-11-03):
+# The transitions below are derived from P Chan's sources, except that the
+# 1973 through 1983 transitions are from Shanks & Pottenger since we have
+# no better data there.
+
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Belize	1918	1942	-	Oct	Sun>=2	0:00	0:30	-0530
-Rule	Belize	1919	1943	-	Feb	Sun>=9	0:00	0	CST
+Rule	Belize	1918	1941	-	Oct	Sat>=1	24:00	0:30	-0530
+Rule	Belize	1919	1942	-	Feb	Sat>=8	24:00	0	CST
+Rule	Belize	1942	only	-	Jun	27	24:00	1:00	CWT
+Rule	Belize	1945	only	-	Aug	14	23:00u	1:00	CPT
+Rule	Belize	1945	only	-	Dec	15	24:00	0	CST
+Rule	Belize	1947	1967	-	Oct	Sat>=1	24:00	0:30	-0530
+Rule	Belize	1948	1968	-	Feb	Sat>=8	24:00	0	CST
 Rule	Belize	1973	only	-	Dec	 5	0:00	1:00	CDT
 Rule	Belize	1974	only	-	Feb	 9	0:00	0	CST
 Rule	Belize	1982	only	-	Dec	18	0:00	1:00	CDT
 Rule	Belize	1983	only	-	Feb	12	0:00	0	CST
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone	America/Belize	-5:52:48 -	LMT	1912 Apr
+Zone	America/Belize	-5:52:48 -	LMT	1912 Apr  1
 			-6:00	Belize	%s
 
 # Bermuda
 
+# From Paul Eggert (2020-11-24):
 # For 1899 Milne gives -4:19:18.3 as the meridian of the clock tower,
-# Bermuda dockyard, Ireland I; round that.
+# Bermuda dockyard, Ireland I.  This agrees with standard offset given in the
+# Daylight Saving Act, 1917 cited below.  Round that to the nearest second.
+# It is not known when this time became standard for Bermuda; guess 1890.
+# The transition to -04 was specified by:
+# 1930: The Time Zone Act, 1929 (1929: No. 39) [1929-11-08]
+# https://books.google.com/books?id=7tdMAQAAIAAJ&pg=RA54-PP1
+
+# From P Chan (2020-11-20):
+# Most of the information can be found online from the Bermuda National
+# Library - Digital Collection which includes The Royal Gazette (RG) until 1957
+# https://bnl.contentdm.oclc.org/digital/
+# I will cite the ID.  For example, [10000] means
+# https://bnl.contentdm.oclc.org/digital/collection/BermudaNP02/id/10000
+#
+# 1917: Apr 5 midnight to Sep 30 midnight
+# Daylight Saving Act, 1917 (1917 No. 13) [1917-04-02]
+# Bermuda Acts and Resolves 1917, p 37-38
+# https://books.google.com/books?id=M-lCAQAAMAAJ&pg=PA36-IA2
+# RG, 1917-04-04, p 6 [42340] gives the spring forward date.
+#
+# 1918: Apr 13 midnight to Sep 15 midnight
+# Daylight Saving Act, 1918 (1918 No. 9) [1918-04-06]
+# Bermuda Acts and Resolves 1917, p 13
+# https://books.google.com/books?id=K-lCAQAAMAAJ&pg=RA1-PA7
+#
+# Note that local mean time was still used before 1930.
+#
+# During WWII, DST was introduced by Defence Regulations
+# 1942: Jan 11 02:00 to Oct 18 02:00 [113646], [115726]
+# 1943: Mar 21 02:00 to Oct 31 02:00 [116704], [118193]
+# 1944: Mar 12 02:00 to Nov 5 02:00 [119225], [121593]
+# 1945: Mar 11 02:00 to Nov 4 02:00 [122369], [124461]
+# RG, 1942-01-08, p 2, 1942-10-12, p 2 , 1943-03-06, p 2, 1943-09-03, p 1,
+# 1944-02-29, p 6, 1944-09-20, p 2, 1945-02-13, p 2, 1945-11-03, p 1
+#
+# In 1946, the House of Assembly rejected DST twice. [128686], [128076]
+# RG, 1946-03-16 p 1,1946-04-13 p 1
+#
+# 1947: third Sunday in May 02:00 to second Sunday in September 02:00
+# DST in 1947 was defined in the Daylight Saving Act, 1947 (1947: No. 12)
+# which expired at the end of the year.  [125784] ,[132405], [144454], [138226]
+# RG, 1947-02-27, p 1, 1947-05-15, p 1, 1947-09-13, p 1, 1947-12-30, p 1
+#
+# 1948-1952: fourth Sunday in May 02:00 to first Sunday in September 02:00
+# DST in 1948 was defined in the Daylight Saving Act, 1948 (1948 : No. 12)
+# which was set to expired at the end of the year but it was extended until
+# the end of 1952 and was not further extended.
+# [129802], [139403], [146008], [135240], [144330], [139049], [143309],
+# [148271], [149773], [153589], [153802], [155924]
+# RG, 1948-04-13, p 1, 1948-05-22, p 1, 1948-09-04, p 1, 1949-05-21, p1,
+# 1949-09-03, p 1, 1950-05-27 p 1, 1950-09-02, p 1, 1951-05-27, p 1,
+# 1951-09-01, p 1, 1952-05-23, p 1, 1952-09-26, p 1, 1952-12-21, p 8
+#
+# In 1953-1955, the House of Assembly rejected DST each year. [158996],
+# [162620], [166720] RG, 1953-05-02, p 1, 1954-04-01 p 1, 1955-03-12, p 1
+#
+# 1956: fourth Sunday in May 02:00 to last Sunday in October 02:00
+# Time Zone (Seasonal Variation) Act, 1956 (1956: No.44) [1956-05-25]
+# Bermuda Public Acts 1956, p 331-332
+# https://books.google.com/books?id=Xs1AlmD_cEwC&pg=PA63
+#
+# The extension of the Act was rejected by the House of Assembly. [176218]
+# RG, 1956-12-13, p 1
+#
+# From the Chronological Table of Public and Private Acts up to 1985, it seems
+# that there does not exist other Acts related to DST before 1973.
+# https://books.google.com/books?id=r9hMAQAAIAAJ&pg=RA23-PA1
+# Public Acts of the Legislature of the Islands of Bermuda, Together with
+# Statutory Instruments in Force Thereunder, Vol VII
 
 # From Dan Jones, reporting in The Royal Gazette (2006-06-26):
-
 # Next year, however, clocks in the US will go forward on the second Sunday
 # in March, until the first Sunday in November.  And, after the Time Zone
 # (Seasonal Variation) Bill 2006 was passed in the House of Assembly on
 # Friday, the same thing will happen in Bermuda.
 # http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135
 
+# Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
+Rule	Bermuda	1917	only	-	Apr	 5	24:00	1:00	-
+Rule	Bermuda	1917	only	-	Sep	30	24:00	0	-
+Rule	Bermuda	1918	only	-	Apr	13	24:00	1:00	-
+Rule	Bermuda	1918	only	-	Sep	15	24:00	0	S
+Rule	Bermuda	1942	only	-	Jan	11	 2:00	1:00	D
+Rule	Bermuda	1942	only	-	Oct	18	 2:00	0	S
+Rule	Bermuda	1943	only	-	Mar	21	 2:00	1:00	D
+Rule	Bermuda	1943	only	-	Oct	31	 2:00	0	S
+Rule	Bermuda	1944	1945	-	Mar	Sun>=8	 2:00	1:00	D
+Rule	Bermuda	1944	1945	-	Nov	Sun>=1	 2:00	0	S
+Rule	Bermuda	1947	only	-	May	Sun>=15	 2:00	1:00	D
+Rule	Bermuda	1947	only	-	Sep	Sun>=8	 2:00	0	S
+Rule	Bermuda	1948	1952	-	May	Sun>=22	 2:00	1:00	D
+Rule	Bermuda	1948	1952	-	Sep	Sun>=1	 2:00	0	S
+Rule	Bermuda	1956	only	-	May	Sun>=22	 2:00	1:00	D
+Rule	Bermuda	1956	only	-	Oct	lastSun	 2:00	0	S
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone Atlantic/Bermuda	-4:19:18 -	LMT	1930 Jan  1  2:00 # Hamilton
-			-4:00	-	AST	1974 Apr 28  2:00
+Zone Atlantic/Bermuda	-4:19:18 -	LMT	1890	# Hamilton
+			-4:19:18 Bermuda BMT/BST 1930 Jan 1  2:00
+			-4:00	Bermuda	A%sT	1974 Apr 28  2:00
 			-4:00	Canada	A%sT	1976
 			-4:00	US	A%sT
 
@@ -3574,7 +3727,7 @@ Zone America/Miquelon	-3:44:40 -	LMT	1911 May 15 # St Pierre
 # "Eastern Standard Times Begins 2007
 # Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time"
 # indicating that the normal ET rules are followed.
-#
+
 # From Paul Eggert (2014-08-19):
 # The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round.  See:
 # http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm
@@ -3589,19 +3742,42 @@ Zone America/Miquelon	-3:44:40 -	LMT	1911 May 15 # St Pierre
 # during the summer months and Standard Time, also known as Local
 # Time, during the winter months with effect from April 2018 ...
 # https://www.gov.uk/government/news/turks-and-caicos-post-cabinet-meeting-statement--3
-#
 # From Paul Eggert (2017-08-26):
 # The date of effect of the spring 2018 change appears to be March 11,
 # which makes more sense.  See: Hamilton D. Time change back
 # by March 2018 for TCI. Magnetic Media. 2017-08-25.
 # http://magneticmediatv.com/2017/08/time-change-back-by-march-2018-for-tci/
 #
+# From P Chan (2020-11-27):
+# Standard Time Declaration Order 2015 (L.N. 15/2015)
+# http://online.fliphtml5.com/fizd/czin/#p=2
+#
+# Standard Time Declaration Order 2017 (L.N. 31/2017)
+# http://online.fliphtml5.com/fizd/dmcu/#p=2
+#
+# From Tim Parenti (2020-12-05):
+# Although L.N. 31/2017 reads that it "shall come into operation at 2:00 a.m.
+# on 11th March 2018", a precise interpretation here poses some problems.  The
+# order states that "the standard time to be observed throughout the Turks and
+# Caicos Islands shall be the same time zone as the Eastern United States of
+# America" and further clarifies "[f]or the avoidance of doubt" that it
+# "applies to the Eastern Standard Time as well as any changes thereto for
+# Daylight Saving Time."  However, as clocks in Turks and Caicos approached
+# 02:00 -04, and thus the declared implementation time, it was still 01:00 EST
+# (-05), as DST in the Eastern US would not start until an hour later.
+#
+# Since it is unlikely that those on the islands switched their clocks twice in
+# the span of an hour, we assume instead that the adoption of EDT actually took
+# effect once clocks in the Eastern US had sprung forward, from 03:00 -04.
+# This discrepancy only affects the time zone abbreviation and DST flag for the
+# intervening hour, not wall clock times, as -04 was maintained throughout.
+
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
 Zone America/Grand_Turk	-4:44:32 -	LMT	1890
 			-5:07:10 -	KMT	1912 Feb # Kingston Mean Time
 			-5:00	-	EST	1979
-			-5:00	US	E%sT	2015 Nov Sun>=1 2:00
-			-4:00	-	AST	2018 Mar 11 3:00
+			-5:00	US	E%sT	2015 Mar  8  2:00
+			-4:00	-	AST	2018 Mar 11  3:00
 			-5:00	US	E%sT
 
 # British Virgin Is
diff --git a/theory.html b/theory.html
index 4613799..28f6b8e 100644
--- a/theory.html
+++ b/theory.html
@@ -474,8 +474,8 @@ in decreasing order of importance:
     <p>
     <small>These abbreviations are:
       AMT Amsterdam, Asunción, Athens;
-      BMT Baghdad, Bangkok, Batavia, Bern, Bogotá, Bridgetown, Brussels,
-	Bucharest;
+      BMT Baghdad, Bangkok, Batavia, Bermuda, Bern, Bogotá, Bridgetown,
+        Brussels, Bucharest;
       CMT Calamarca, Caracas, Chisinau, Colón, Copenhagen, Córdoba;
       DMT Dublin/Dunsink;
       EMT Easter;
@@ -506,6 +506,7 @@ in decreasing order of importance:
     <small>A few abbreviations also follow the pattern that
     <abbr>GMT</abbr>/<abbr>BST</abbr> established for time in the UK.
     They are:
+      BMT/BST for Bermuda 1890&ndash;1930,
       CMT/BST for Calamarca Mean Time and Bolivian Summer Time
 	1890&ndash;1932,
       DMT/IST for Dublin/Dunsink Mean Time and Irish Summer Time
diff --git a/tz-link.html b/tz-link.html
index 10c40b5..56ef9e4 100644
--- a/tz-link.html
+++ b/tz-link.html
@@ -1034,8 +1034,21 @@ title="International Earth Rotation and Reference Systems Service">IERS</abbr>
 Bulletins</a> contains official publications of the International
 Earth Rotation and Reference Systems Service, which decides when leap
 seconds occur. The <code><abbr>tz</abbr></code> code and data support leap seconds
-via an optional "<code>right</code>" configuration, as opposed to the
-default "<code>posix</code>" configuration.</li>
+via an optional "<code>right</code>" configuration where a computer's internal
+<code>time_t</code> integer clock counts every <abbr>TAI</abbr> second,
+as opposed to the default "<code>posix</code>" configuration
+where the internal clock ignores leap seconds.
+The two configurations agree for timestamps starting with 1972-01-01 00:00:00
+<abbr>UTC</abbr> (<code>time_t</code> 63&thinsp;072&thinsp;000) and diverge for
+timestamps starting with <code>time_t</code> 78&thinsp;796&thinsp;800,
+which corresponds to the first leap second
+1972-06-30 23:59:60 <abbr>UTC</abbr> in the "<code>right</code>" configuration,
+and to
+1972-07-01 00:00:00 <abbr>UTC</abbr> in the "<code>posix</code>" configuration.
+In practice the two configurations also agree for timestamps before
+1972 even though the historical situation is messy, partly because
+neither <abbr>UTC</abbr> nor <abbr>TAI</abbr>
+is well-defined for sufficiently-old timestamps.</li>
 <li><a href="https://developers.google.com/time/smear">Leap Smear</a>
 discusses how to gradually adjust <abbr>POSIX</abbr> clocks near a
 leap second so that they disagree with <abbr>UTC</abbr> by at most a
@@ -1048,7 +1061,7 @@ cloud service providers. However, according to
 <a href="https://tools.ietf.org/html/rfc8633#section-3.7.1">&sect;3.7.1 of
 Network Time Protocol Best Current Practices</a>
 (Internet <abbr>RFC</abbr> 8633), leap smearing is not suitable for
-applications requiring accurate UTC or civil time,
+applications requiring accurate <abbr>UTC</abbr> or civil time,
 and is intended for use only in single, well-controlled environments.</li>
 <li>The <a
 href="https://pairlist6.pair.net/mailman/listinfo/leapsecs">Leap
diff --git a/zic.8 b/zic.8
index dcd2fa3..60262d7 100644
--- a/zic.8
+++ b/zic.8
@@ -590,6 +590,42 @@ first transition into standard time.
 In a single zone it is an error if two rules take effect at the same
 instant, or if two zone changes take effect at the same instant.
 .PP
+If a continuation line subtracts
+.I N
+seconds from the UT offset after a transition that would be
+interpreted to be later if using the continuation line's UT offset and
+rules, the
+.q "until"
+time of the previous zone or continuation line is interpreted
+according to the continuation line's UT offset and rules, and any rule
+that would otherwise take effect in the next
+.I N
+seconds is instead assumed to take effect simultaneously.
+For example:
+.br
+.ne 7
+.nf
+.in +2m
+.ta \w'# Rule\0\0'u +\w'NAME\0\0'u +\w'FROM\0\0'u +\w'2006\0\0'u +\w'\*-\0\0'u +\w'Oct\0\0'u +\w'lastSun\0\0'u +\w'2:00\0\0'u +\w'SAVE\0\0'u
+.sp
+# Rule	NAME	FROM	TO	\*-	IN	ON	AT	SAVE	LETTER/S
+Rule	US	1967	2006	-	Oct	lastSun	2:00	0	S
+Rule	US	1967	1973	-	Apr	lastSun	2:00	1:00	D
+.ta \w'Zone\0\0America/Menominee\0\0'u +\w'STDOFF\0\0'u +\w'RULES\0\0'u +\w'FORMAT\0\0'u
+# Zone\0\0NAME	STDOFF	RULES	FORMAT	[UNTIL]
+Zone\0\0America/Menominee	\*-5:00	\*-	EST	1973 Apr 29 2:00
+	\*-6:00	US	C%sT
+.sp
+.in
+.fi
+Here, an incorrect reading would be there were two clock changes on 1973-04-29,
+the first from 02:00 EST (\*-05) to 01:00 CST (\*-06),
+and the second an hour later from 02:00 CST (\*-06) to 03:00 CDT (\*-05).
+However,
+.B zic
+interprets this more sensibly as a single transition from 02:00 CST (\*-05) to
+02:00 CDT (\*-05).
+.PP
 A link line has the form
 .sp
 .nf
diff --git a/zone.tab b/zone.tab
index 8d056e3..1f0128f 100644
--- a/zone.tab
+++ b/zone.tab
@@ -56,8 +56,7 @@ AS	-1416-17042	Pacific/Pago_Pago
 AT	+4813+01620	Europe/Vienna
 AU	-3133+15905	Australia/Lord_Howe	Lord Howe Island
 AU	-5430+15857	Antarctica/Macquarie	Macquarie Island
-AU	-4253+14719	Australia/Hobart	Tasmania (most areas)
-AU	-3956+14352	Australia/Currie	Tasmania (King Island)
+AU	-4253+14719	Australia/Hobart	Tasmania
 AU	-3749+14458	Australia/Melbourne	Victoria
 AU	-3352+15113	Australia/Sydney	New South Wales (most areas)
 AU	-3157+14127	Australia/Broken_Hill	New South Wales (Yancowinna)
@@ -130,9 +129,9 @@ CA	+682059-1334300	America/Inuvik	Mountain - NT (west)
 CA	+4906-11631	America/Creston	MST - BC (Creston)
 CA	+5946-12014	America/Dawson_Creek	MST - BC (Dawson Cr, Ft St John)
 CA	+5848-12242	America/Fort_Nelson	MST - BC (Ft Nelson)
+CA	+6043-13503	America/Whitehorse	MST - Yukon (east)
+CA	+6404-13925	America/Dawson	MST - Yukon (west)
 CA	+4916-12307	America/Vancouver	Pacific - BC (most areas)
-CA	+6043-13503	America/Whitehorse	Pacific - Yukon (east)
-CA	+6404-13925	America/Dawson	Pacific - Yukon (west)
 CC	-1210+09655	Indian/Cocos
 CD	-0418+01518	Africa/Kinshasa	Dem. Rep. of Congo (west)
 CD	-1140+02728	Africa/Lubumbashi	Dem. Rep. of Congo (east)
@@ -337,8 +336,8 @@ RU	+554521+0373704	Europe/Moscow	MSK+00 - Moscow area
 # Programs should use zone1970.tab instead; see above.
 UA	+4457+03406	Europe/Simferopol	Crimea
 RU	+5836+04939	Europe/Kirov	MSK+00 - Kirov
+RU	+4844+04425	Europe/Volgograd	MSK+00 - Volgograd
 RU	+4621+04803	Europe/Astrakhan	MSK+01 - Astrakhan
-RU	+4844+04425	Europe/Volgograd	MSK+01 - Volgograd
 RU	+5134+04602	Europe/Saratov	MSK+01 - Saratov
 RU	+5420+04824	Europe/Ulyanovsk	MSK+01 - Ulyanovsk
 RU	+5312+05009	Europe/Samara	MSK+01 - Samara, Udmurtia
diff --git a/zone1970.tab b/zone1970.tab
index 53ee77e..396e4d3 100644
--- a/zone1970.tab
+++ b/zone1970.tab
@@ -63,8 +63,7 @@ AS,UM	-1416-17042	Pacific/Pago_Pago	Samoa, Midway
 AT	+4813+01620	Europe/Vienna
 AU	-3133+15905	Australia/Lord_Howe	Lord Howe Island
 AU	-5430+15857	Antarctica/Macquarie	Macquarie Island
-AU	-4253+14719	Australia/Hobart	Tasmania (most areas)
-AU	-3956+14352	Australia/Currie	Tasmania (King Island)
+AU	-4253+14719	Australia/Hobart	Tasmania
 AU	-3749+14458	Australia/Melbourne	Victoria
 AU	-3352+15113	Australia/Sydney	New South Wales (most areas)
 AU	-3157+14127	Australia/Broken_Hill	New South Wales (Yancowinna)
@@ -127,9 +126,9 @@ CA	+682059-1334300	America/Inuvik	Mountain - NT (west)
 CA	+4906-11631	America/Creston	MST - BC (Creston)
 CA	+5946-12014	America/Dawson_Creek	MST - BC (Dawson Cr, Ft St John)
 CA	+5848-12242	America/Fort_Nelson	MST - BC (Ft Nelson)
+CA	+6043-13503	America/Whitehorse	MST - Yukon (east)
+CA	+6404-13925	America/Dawson	MST - Yukon (west)
 CA	+4916-12307	America/Vancouver	Pacific - BC (most areas)
-CA	+6043-13503	America/Whitehorse	Pacific - Yukon (east)
-CA	+6404-13925	America/Dawson	Pacific - Yukon (west)
 CC	-1210+09655	Indian/Cocos
 CH,DE,LI	+4723+00832	Europe/Zurich	Swiss time
 CI,BF,GM,GN,ML,MR,SH,SL,SN,TG	+0519-00402	Africa/Abidjan
@@ -292,8 +291,8 @@ RU	+554521+0373704	Europe/Moscow	MSK+00 - Moscow area
 # Mention RU and UA alphabetically.  See "territorial claims" above.
 RU,UA	+4457+03406	Europe/Simferopol	Crimea
 RU	+5836+04939	Europe/Kirov	MSK+00 - Kirov
+RU	+4844+04425	Europe/Volgograd	MSK+00 - Volgograd
 RU	+4621+04803	Europe/Astrakhan	MSK+01 - Astrakhan
-RU	+4844+04425	Europe/Volgograd	MSK+01 - Volgograd
 RU	+5134+04602	Europe/Saratov	MSK+01 - Saratov
 RU	+5420+04824	Europe/Ulyanovsk	MSK+01 - Ulyanovsk
 RU	+5312+05009	Europe/Samara	MSK+01 - Samara, Udmurtia
author	Stuart Bishop <stuart.bishop@canonical.com>	2020-12-25 07:42:52 +1100
committer	Stuart Bishop <stuart.bishop@canonical.com>	2020-12-25 07:42:52 +1100
commit	aaef58a8e40d7e6bd70f2d4ce347caa772510e59 (patch)
tree	f30c29def341fdcb502e575c5a9441e4567a55c2
parent	a4a62d8d41eea2df3759cbcdbd9100a72e8c28c7 (diff)
download	pytz-git-aaef58a8e40d7e6bd70f2d4ce347caa772510e59.tar.gz