On 3/18/25 06:04, Roozbeh Pournader via tz wrote:
I hunted down the exact time of Iran's transition from +0400 to +0330.
Thanks for doing that. I installed the attached proposed patch to the
development repository.
It appears that the 1978-11-10 change from +04 to +0330 was at midnight
between Friday and Saturday, whereas the 1977-10-20 change from +0430 to
+04 was at midnight between Thursday and Friday. Historically, both
Thursday/Friday and Friday/Saturday transitions have been reported in
nearby countries (e.g., Jordan) so they're both plausible here.From 4878fa40ec93499d3a7e265cd8e0ff52237ada75 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email protected]>
Date: Tue, 18 Mar 2025 11:42:21 -0700
Subject: [PROPOSED] Iran switched to +0330 on 1978-11-10 at 24:00
(Thanks to Roozbeh Pournader.)
* NEWS: Mention this.
* asia (Asia/Tehran): Switch to 3:30 at 1978 Nov 10 24:00,
not the vague "1979".
---
NEWS | 5 +++++
asia | 12 +++++++++++-
2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/NEWS b/NEWS
index eec41543..e3713746 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,11 @@ News for the tz database
Unreleased, experimental changes
+ Changes to past timestamps
+
+ Iran switched from +04 to +0330 on 1978-11-10 at 24:00, not at
+ year end. (Thanks to Roozbeh Pournader.)
+
Changes to code
'zic -l TIMEZONE -d . -l /some/other/file/system' no longer has a
diff --git a/asia b/asia
index d4eb0580..d3d1059a 100644
--- a/asia
+++ b/asia
@@ -1500,6 +1500,16 @@ Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov
# (UIT No. 143 17.XI.1977) and not 23 September (UIT No. 141 13.IX.1977).
# UIT is the Operational Bulletin of International Telecommunication Union.
+# From Roozbeh Pournader (2025-03-18):
+# ... the exact time of Iran's transition from +0400 to +0330 ... was Friday
+# 1357/8/19 AP=1978-11-10. Here's a newspaper clip from the Ettela'at
+# newspaper, dated 1357/8/14 AP=1978-11-05, translated from Persian
+# (at https://w.wiki/DUEY):
+# Following the government's decision about returning the official time
+# to the previous status, the spokesperson for the Ministry of Energy
+# announced today: At the hour 24 of Friday 19th of Aban (=1978-11-10),
+# the country's time will be pulled back half an hour.
+#
# From Roozbeh Pournader (2003-03-15):
# This is an English translation of what I just found (originally in Persian).
# The Gregorian dates in brackets are mine:
@@ -1627,7 +1637,7 @@ Rule Iran 2021 2022 - Sep 21 24:00 0 -
Zone Asia/Tehran 3:25:44 - LMT 1916
3:25:44 - TMT 1935 Jun 13 # Tehran Mean Time
3:30 Iran %z 1977 Oct 20 24:00
- 4:00 Iran %z 1979
+ 4:00 Iran %z 1978 Nov 10 24:00
3:30 Iran %z
--
2.48.1
