From ddcb5fa20791c3c5f1a15194091aacb732642da2 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 11 Jun 2026 14:35:13 -0700 Subject: [PROPOSED] Alberta has stopped changing clocks (Thanks to Roozbeh Bournader and others.) * NEWS: Mention this. * northamerica (America/Edmonton): Now permanently on -06. Model this with abbreviation CST. Temporarily model the the transition on 2026-11-01 at 02:00. The actual transition is on 2026-09-01 but we can delay this due to the same CLDR problems that we saw with BC. Also mention the potential impacts in portions of southeastern British Columbia which have followed Edmonton. * zone.tab, zone1970.tab, zonenow.tab: Update comments. --- NEWS | 12 ++++++++++++ northamerica | 36 ++++++++++++++++++++++++++++++++++-- zone.tab | 2 +- zone1970.tab | 2 +- zonenow.tab | 5 ++++- 5 files changed, 52 insertions(+), 5 deletions(-) diff --git a/NEWS b/NEWS index 6aeda69f..466a8a2e 100644 --- a/NEWS +++ b/NEWS @@ -2,6 +2,18 @@ News for the tz database Unreleased, experimental changes + Briefly: + Alberta moves to permanent -06 on 2026-09-01. + + Changes to future timestamps + + Alberta’s 2026-03-08 spring forward was its last foreseeable clock + change, as it moved to permanent -06 thereafter. (Thanks to + Roozbeh Pournader and others.) Although the change to permanent + -06 is legally scheduled for 2026-09-01, temporarily model the + change to occur on 2026-11-01 at 02:00, for the same reason we + have a similarly temporary hack for British Columbia. + Changes to build procedure The undocumented ‘typecheck’ Makefile check rule has been removed. diff --git a/northamerica b/northamerica index 992095e8..c8d2eade 100644 --- a/northamerica +++ b/northamerica @@ -1929,6 +1929,30 @@ Zone America/Swift_Current -7:11:20 - LMT 1905 Sep # Boyer JP. Forcing Choice: The Risky Reward of Referendums. Dundum. 2017. # ISBN 978-1459739123. +# From Roozbeh Pournader (2026-04-20): +# https://calgaryherald.com/opinion/columnists/bell-alberta-daylight-time-year-round-premier-danielle-smith +# +# From Tim Parenti (2026-04-23): +# Bill 31, the Red Tape Reduction Statutes Amendment Act, 2026 +# https://docs.assembly.ab.ca/LADDAR_files/docs/bills/bill/legislature_31/session_2/20251023_bill-031.pdf +# would repeal the Daylight Saving Time Act in the Revised Statues of Alberta +# 2000 Chapter D-5: +# https://kings-printer.alberta.ca/documents/Acts/D05.pdf +# ...and substitutes a new chapter with language that closely parallels the +# original. The new title is the Official Time Act and would be numbered +# Chapter O-5.7. The bill would establish a standard time of UTC−6 without +# replacing the language previously used to effectuate DST. +# +# From Cary Sweet (2026-06-11): +# O.C. 170/2026 June 4, 2026 ... +# https://kings-printer.alberta.ca/Documents/Orders/Orders_in_Council/2026/2026_170.html +# From Paul Eggert (2026-06-11): +# Although the change takes effect on 2026-09-01, as a temporary hack pretend +# that it takes effect 2026-11-01 at 02:00. As with America/Vancouver, +# this pretense works around a limitation in CLDR v48.2 (2026-03-17). +# (Below, this temporary hack is marked “Temporary hack; see above.”) +# We should be able to remove the temporary hack after CLDR is fixed. + # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D Rule Edm 1918 only - Oct 27 2:00 0 S @@ -1946,7 +1970,11 @@ Rule Edm 1972 2006 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Edmonton -7:33:52 - LMT 1906 Sep -7:00 Edm M%sT 1987 - -7:00 Canada M%sT + -7:00 Canada M%sT 2026 Sep 1 + # Temporary hack; see above. + -7:00 1:00 MDT 2026 Nov 1 2:00 + # End of temporary hack. + -7:00 - CST # British Columbia @@ -2033,6 +2061,10 @@ Zone America/Edmonton -7:33:52 - LMT 1906 Sep # saying, “Pardon the pun, but this is not a time-sensitive issue.” # For now, merely mention the potential change in these comments. # If it happens it would likely affect clocks starting 2027-03-14 at 02:00. +# From Tim Parenti (2026-05-14): +# RDEK has historically been aligned with neighboring Alberta. With the latter +# now opting to stay on -06 year-round, if RDEK does not follow, it would +# require a new zone for the Cranbrook area. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Vanc 1918 only - Apr 14 2:00 1:00 D @@ -2049,7 +2081,7 @@ Zone America/Vancouver -8:12:28 - LMT 1884 -8:00 Vanc P%sT 1987 -8:00 Canada P%sT 2026 Mar 9 # Temporary hack; see above. - -8:00 1:00 PDT 2026 Nov 1 02:00 + -8:00 1:00 PDT 2026 Nov 1 2:00 # End of temporary hack. -7:00 - MST Zone America/Dawson_Creek -8:00:56 - LMT 1884 diff --git a/zone.tab b/zone.tab index 2ae8a8c4..69d50bd8 100644 --- a/zone.tab +++ b/zone.tab @@ -121,7 +121,7 @@ CA +744144-0944945 America/Resolute Central - NU (Resolute) CA +624900-0920459 America/Rankin_Inlet Central - NU (central) CA +5024-10439 America/Regina CST - SK (most areas) CA +5017-10750 America/Swift_Current CST - SK (midwest) -CA +5333-11328 America/Edmonton Mountain - AB, BC(E), NT(E), SK(W) +CA +5333-11328 America/Edmonton CST - AB, BC(E), NT(E), SK(W) CA +690650-1050310 America/Cambridge_Bay Mountain - NU (west) CA +682059-1334300 America/Inuvik Mountain - NT (west) CA +4916-12307 America/Vancouver MST - BC (most areas) diff --git a/zone1970.tab b/zone1970.tab index a9b47bcb..635eabcb 100644 --- a/zone1970.tab +++ b/zone1970.tab @@ -112,7 +112,7 @@ CA +744144-0944945 America/Resolute Central - NU (Resolute) CA +624900-0920459 America/Rankin_Inlet Central - NU (central) CA +5024-10439 America/Regina CST - SK (most areas) CA +5017-10750 America/Swift_Current CST - SK (midwest) -CA +5333-11328 America/Edmonton Mountain - AB, BC(E), NT(E), SK(W) +CA +5333-11328 America/Edmonton CST - AB, BC(E), NT(E), SK(W) CA +690650-1050310 America/Cambridge_Bay Mountain - NU (west) CA +682059-1334300 America/Inuvik Mountain - NT (west) CA +4916-12307 America/Vancouver MST - BC (most areas) diff --git a/zonenow.tab b/zonenow.tab index 54e4485d..b4144bfc 100644 --- a/zonenow.tab +++ b/zonenow.tab @@ -59,7 +59,7 @@ XX -2504-13005 Pacific/Pitcairn Pitcairn XX +340308-1181434 America/Los_Angeles Pacific (PST/PDT) - US & Canada; Mexico near US border # # -08/-07 - PST/PDT (North America DST) until 2026-11-01 02:00; then MST -XX +4916-12307 America/Vancouver MST - BC (most areas) +XX +4916-12307 America/Vancouver Mountain Standard (MST) - British Columbia (most areas) # # -07 - MST XX +332654-1120424 America/Phoenix Mountain Standard (MST) - Arizona; western Mexico; Yukon @@ -67,6 +67,9 @@ XX +332654-1120424 America/Phoenix Mountain Standard (MST) - Arizona; western Me # -07/-06 - MST/MDT (North America DST) XX +394421-1045903 America/Denver Mountain (MST/MDT) - US & Canada; Mexico near US border # +# -07/-06 - MST/MDT (North America DST) until 2026-11-01 02:00; then CST +XX +5333-11328 America/Edmonton Central Standard (CST) - Alberta and some neighbors +# # -06 XX -0054-08936 Pacific/Galapagos Galápagos # -- 2.54.0