From f29068291ce6aab45700c0ee9e6870b6620ed608 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Fri, 30 Sep 2022 11:35:30 -0700
Subject: [PATCH 2/2] Prefer UT for whole-hour UT transitions
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Prefer Universal Time for transitions out of local mean time to a
local time that is on the hour.  For example, instead of saying
that America/Chicago’s 1883-11-18 transition from -05:50:36 to -06
was at 12:09:24 local time, say that it was at 18:00 UT.  This is
easier to maintain and this style should help avoid bugs like the
one just fixed for Tijuana.  This change does not affect the
actual transitions (e.g., the output TZif files are unaffected).
* europe (Africa/Ceuta):
* northamerica (America/Chicago, America/North_Dakota/Center)
(America/North_Dakota/New_Salem, America/North_Dakota/Beulah)
(America/Denver, America/Los_Angeles, America/Phoenix)
(America/Phoenix, America/Boise, America/Indiana/Indianapolis)
(America/Indiana/Marengo, America/Indiana/Vincennes)
(America/Indiana/Tell_City, America/Indiana/Petersburg)
(America/Indiana/Knox, America/Indiana/Winamac)
(America/Indiana/Vevay, America/Kentucky/Louisville)
(America/Kentucky/Monticello):
Prefer UT for time of transition out of LMT.
---
 europe       |  2 +-
 northamerica | 36 ++++++++++++++++++------------------
 2 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/europe b/europe
index bb0c7cfd..621495ce 100644
--- a/europe
+++ b/europe
@@ -3394,7 +3394,7 @@ Zone	Europe/Madrid	-0:14:44 -	LMT	1901 Jan  1  0:00u
 			 0:00	Spain	WE%sT	1940 Mar 16 23:00
 			 1:00	Spain	CE%sT	1979
 			 1:00	EU	CE%sT
-Zone	Africa/Ceuta	-0:21:16 -	LMT	1900 Dec 31 23:38:44
+Zone	Africa/Ceuta	-0:21:16 -	LMT	1901 Jan  1  0:00u
 			 0:00	-	WET	1918 May  6 23:00
 			 0:00	1:00	WEST	1918 Oct  7 23:00
 			 0:00	-	WET	1924
diff --git a/northamerica b/northamerica
index ea1b2c0e..da84f354 100644
--- a/northamerica
+++ b/northamerica
@@ -439,7 +439,7 @@ Rule	Chicago	1922	1966	-	Apr	lastSun	2:00	1:00	D
 Rule	Chicago	1922	1954	-	Sep	lastSun	2:00	0	S
 Rule	Chicago	1955	1966	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 12:09:24
+Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1920
 			-6:00	Chicago	C%sT	1936 Mar  1  2:00
 			-5:00	-	EST	1936 Nov 15  2:00
@@ -448,7 +448,7 @@ Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 12:09:24
 			-6:00	Chicago	C%sT	1967
 			-6:00	US	C%sT
 # Oliver County, ND switched from mountain to central time on 1992-10-25.
-Zone America/North_Dakota/Center -6:45:12 - LMT	1883 Nov 18 12:14:48
+Zone America/North_Dakota/Center -6:45:12 - LMT	1883 Nov 18 19:00u
 			-7:00	US	M%sT	1992 Oct 25  2:00
 			-6:00	US	C%sT
 # Morton County, ND, switched from mountain to central time on
@@ -458,7 +458,7 @@ Zone America/North_Dakota/Center -6:45:12 - LMT	1883 Nov 18 12:14:48
 # Jones, Mellette, and Todd Counties in South Dakota;
 # but in practice these other counties were already observing central time.
 # See <http://www.epa.gov/fedrgstr/EPA-IMPACT/2003/October/Day-28/i27056.htm>.
-Zone America/North_Dakota/New_Salem -6:45:39 - LMT	1883 Nov 18 12:14:21
+Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 19:00u
 			-7:00	US	M%sT	2003 Oct 26  2:00
 			-6:00	US	C%sT
 
@@ -475,7 +475,7 @@ Zone America/North_Dakota/New_Salem -6:45:39 - LMT	1883 Nov 18 12:14:21
 # largest city in Mercer County).  Google Maps places Beulah's city hall
 # at 47° 15' 51" N, 101° 46' 40" W, which yields an offset of 6h47'07".
 
-Zone America/North_Dakota/Beulah -6:47:07 - LMT	1883 Nov 18 12:12:53
+Zone America/North_Dakota/Beulah -6:47:07 - LMT	1883 Nov 18 19:00u
 			-7:00	US	M%sT	2010 Nov  7  2:00
 			-6:00	US	C%sT
 
@@ -507,7 +507,7 @@ Rule	Denver	1921	only	-	May	22	2:00	0	S
 Rule	Denver	1965	1966	-	Apr	lastSun	2:00	1:00	D
 Rule	Denver	1965	1966	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Denver	-6:59:56 -	LMT	1883 Nov 18 12:00:04
+Zone America/Denver	-6:59:56 -	LMT	1883 Nov 18 19:00u
 			-7:00	US	M%sT	1920
 			-7:00	Denver	M%sT	1942
 			-7:00	US	M%sT	1946
@@ -560,7 +560,7 @@ Rule	CA	1950	1966	-	Apr	lastSun	1:00	1:00	D
 Rule	CA	1950	1961	-	Sep	lastSun	2:00	0	S
 Rule	CA	1962	1966	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Los_Angeles -7:52:58 -	LMT	1883 Nov 18 12:07:02
+Zone America/Los_Angeles -7:52:58 -	LMT	1883 Nov 18 20:00u
 			-8:00	US	P%sT	1946
 			-8:00	CA	P%sT	1967
 			-8:00	US	P%sT
@@ -822,7 +822,7 @@ Zone Pacific/Honolulu	-10:31:26 -	LMT	1896 Jan 13 12:00
 # Go with the Arizona State Library instead.
 
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Phoenix	-7:28:18 -	LMT	1883 Nov 18 11:31:42
+Zone America/Phoenix	-7:28:18 -	LMT	1883 Nov 18 19:00u
 			-7:00	US	M%sT	1944 Jan  1  0:01
 			-7:00	-	MST	1944 Apr  1  0:01
 			-7:00	US	M%sT	1944 Oct  1  0:01
@@ -850,7 +850,7 @@ Link America/Phoenix America/Creston
 # switched four weeks late in 1974.
 #
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Boise	-7:44:49 -	LMT	1883 Nov 18 12:15:11
+Zone America/Boise	-7:44:49 -	LMT	1883 Nov 18 20:00u
 			-8:00	US	P%sT	1923 May 13  2:00
 			-7:00	US	M%sT	1974
 			-7:00	-	MST	1974 Feb  3  2:00
@@ -922,7 +922,7 @@ Rule Indianapolis 1941	only	-	Jun	22	2:00	1:00	D
 Rule Indianapolis 1941	1954	-	Sep	lastSun	2:00	0	S
 Rule Indianapolis 1946	1954	-	Apr	lastSun	2:00	1:00	D
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Indianapolis -5:44:38 - LMT	1883 Nov 18 12:15:22
+Zone America/Indiana/Indianapolis -5:44:38 - LMT 1883 Nov 18 18:00u
 			-6:00	US	C%sT	1920
 			-6:00 Indianapolis C%sT	1942
 			-6:00	US	C%sT	1946
@@ -942,7 +942,7 @@ Rule	Marengo	1951	only	-	Sep	lastSun	2:00	0	S
 Rule	Marengo	1954	1960	-	Apr	lastSun	2:00	1:00	D
 Rule	Marengo	1954	1960	-	Sep	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Marengo -5:45:23 -	LMT	1883 Nov 18 12:14:37
+Zone America/Indiana/Marengo -5:45:23 -	LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1951
 			-6:00	Marengo	C%sT	1961 Apr 30  2:00
 			-5:00	-	EST	1969
@@ -966,7 +966,7 @@ Rule Vincennes	1960	only	-	Oct	lastSun	2:00	0	S
 Rule Vincennes	1961	only	-	Sep	lastSun	2:00	0	S
 Rule Vincennes	1962	1963	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Vincennes -5:50:07 - LMT	1883 Nov 18 12:09:53
+Zone America/Indiana/Vincennes -5:50:07 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1946
 			-6:00 Vincennes	C%sT	1964 Apr 26  2:00
 			-5:00	-	EST	1969
@@ -986,7 +986,7 @@ Rule Perry	1955	1960	-	Sep	lastSun	2:00	0	S
 Rule Perry	1956	1963	-	Apr	lastSun	2:00	1:00	D
 Rule Perry	1961	1963	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Tell_City -5:47:03 - LMT	1883 Nov 18 12:12:57
+Zone America/Indiana/Tell_City -5:47:03 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1946
 			-6:00 Perry	C%sT	1964 Apr 26  2:00
 			-5:00	-	EST	1967 Oct 29  2:00
@@ -1003,7 +1003,7 @@ Rule	Pike	1955	1960	-	Sep	lastSun	2:00	0	S
 Rule	Pike	1956	1964	-	Apr	lastSun	2:00	1:00	D
 Rule	Pike	1961	1964	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Petersburg -5:49:07 - LMT	1883 Nov 18 12:10:53
+Zone America/Indiana/Petersburg -5:49:07 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1955
 			-6:00	Pike	C%sT	1965 Apr 25  2:00
 			-5:00	-	EST	1966 Oct 30  2:00
@@ -1025,7 +1025,7 @@ Rule	Starke	1955	1956	-	Oct	lastSun	2:00	0	S
 Rule	Starke	1957	1958	-	Sep	lastSun	2:00	0	S
 Rule	Starke	1959	1961	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Knox -5:46:30 -	LMT	1883 Nov 18 12:13:30
+Zone America/Indiana/Knox -5:46:30 -	LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1947
 			-6:00	Starke	C%sT	1962 Apr 29  2:00
 			-5:00	-	EST	1963 Oct 27  2:00
@@ -1041,7 +1041,7 @@ Rule	Pulaski	1946	1954	-	Sep	lastSun	2:00	0	S
 Rule	Pulaski	1955	1956	-	Oct	lastSun	2:00	0	S
 Rule	Pulaski	1957	1960	-	Sep	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Winamac -5:46:25 - LMT	1883 Nov 18 12:13:35
+Zone America/Indiana/Winamac -5:46:25 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1946
 			-6:00	Pulaski	C%sT	1961 Apr 30  2:00
 			-5:00	-	EST	1969
@@ -1052,7 +1052,7 @@ Zone America/Indiana/Winamac -5:46:25 - LMT	1883 Nov 18 12:13:35
 #
 # Switzerland County, Indiana, did not observe DST from 1973 through 2005.
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Indiana/Vevay -5:40:16 -	LMT	1883 Nov 18 12:19:44
+Zone America/Indiana/Vevay -5:40:16 -	LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1954 Apr 25  2:00
 			-5:00	-	EST	1969
 			-5:00	US	E%sT	1973
@@ -1088,7 +1088,7 @@ Rule Louisville	1950	1961	-	Apr	lastSun	2:00	1:00	D
 Rule Louisville	1950	1955	-	Sep	lastSun	2:00	0	S
 Rule Louisville	1956	1961	-	Oct	lastSun	2:00	0	S
 # Zone	NAME		STDOFF	RULES	FORMAT	[UNTIL]
-Zone America/Kentucky/Louisville -5:43:02 -	LMT	1883 Nov 18 12:16:58
+Zone America/Kentucky/Louisville -5:43:02 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1921
 			-6:00 Louisville C%sT	1942
 			-6:00	US	C%sT	1946
@@ -1122,7 +1122,7 @@ Zone America/Kentucky/Louisville -5:43:02 -	LMT	1883 Nov 18 12:16:58
 # Federal Register 65, 160 (2000-08-17), pp 50154-50158.
 # https://www.gpo.gov/fdsys/pkg/FR-2000-08-17/html/00-20854.htm
 #
-Zone America/Kentucky/Monticello -5:39:24 - LMT	1883 Nov 18 12:20:36
+Zone America/Kentucky/Monticello -5:39:24 - LMT	1883 Nov 18 18:00u
 			-6:00	US	C%sT	1946
 			-6:00	-	CST	1968
 			-6:00	US	C%sT	2000 Oct 29  2:00
-- 
2.34.1

