FW: FW: Corrections to historic German timezone information

[Paul Eggert]

> Von: Sebastian Wangnick [mailto:sebastian.nospam01 at wangnick.de] 
> Gesendet: Dienstag, 29. Januar 2008 19:18

> However, if you can maintain only one timezone for the state of
> Germany, you should probably use the new definition of
> Europe/Berlin, limiting the error in 1945 to the smaller territory
> and population, but please note that this would be considered
> politically incorrect by said population.

We try to avoid political disputes like that, since that really isn't
what we're interested in and it would be a big time sink for us to
wade into political disputes.  What we mostly care about is describing
the clocks accurately for the regions in question.

It seems to me that the political issue here might be addressed better
simply by treating Berlin more like other occupied cities.  If you
look at the rules for Paris, you'll see that it switches from "France"
to "C-Eur" rules during German occupation.  For Berlin, it would make
sense for it to switch from "C-Eur" to Soviet rules when the Soviets
imposed their own DST rules.

Something like the following change, perhaps?  (I haven't checked it
in detail.)  The idea is that this won't change the externally-visible
behavior of tz time stamps at all; it'll just change how it's
explained.

--- europe	2007/12/31 15:23:09	2007.11
+++ europe	2008/02/05 23:01:27
@@ -480,9 +480,10 @@ Rule	C-Eur	1940	only	-	Apr	 1	 2:00s	1:0
 Rule	C-Eur	1942	only	-	Nov	 2	 2:00s	0	-
 Rule	C-Eur	1943	only	-	Mar	29	 2:00s	1:00	S
 Rule	C-Eur	1943	only	-	Oct	 4	 2:00s	0	-
-Rule	C-Eur	1944	only	-	Apr	 3	 2:00s	1:00	S
+Rule	C-Eur	1944	1945	-	Apr	Mon>=1	 2:00s	1:00	S
 # Whitman gives 1944 Oct 7; go with Shanks & Pottenger.
 Rule	C-Eur	1944	only	-	Oct	 2	 2:00s	0	-
+Rule	C-Eur	1945	only	-	Sep	16	 2:00	0	-
 Rule	C-Eur	1977	1980	-	Apr	Sun>=1	 2:00s	1:00	S
 Rule	C-Eur	1977	only	-	Sep	lastSun	 2:00s	0	-
 Rule	C-Eur	1978	only	-	Oct	 1	 2:00s	0	-
@@ -1105,21 +1106,26 @@ Zone	Europe/Paris	0:09:21 -	LMT	1891 Mar
 
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-Rule	Germany	1945	only	-	Apr	 2	2:00s	1:00	S
-Rule	Germany	1945	only	-	May	24	2:00	2:00	M # Midsummer
-Rule	Germany	1945	only	-	Sep	24	3:00	1:00	S
-Rule	Germany	1945	only	-	Nov	18	2:00s	0	-
 Rule	Germany	1946	only	-	Apr	14	2:00s	1:00	S
 Rule	Germany	1946	only	-	Oct	 7	2:00s	0	-
 Rule	Germany	1947	1949	-	Oct	Sun>=1	2:00s	0	-
-Rule	Germany	1947	only	-	Apr	 6	2:00s	1:00	S
+# http://www.ptb.de/de/org/4/44/441/salt.htm says the following transition
+# occurred at 3:00 MEZ, not the 2:00 MEZ given in Shanks & Pottenger.
+# Go with the PTB.
+Rule	Germany	1947	only	-	Apr	 6	3:00s	1:00	S
 Rule	Germany	1947	only	-	May	11	2:00s	2:00	M
 Rule	Germany	1947	only	-	Jun	29	3:00	1:00	S
 Rule	Germany	1948	only	-	Apr	18	2:00s	1:00	S
 Rule	Germany	1949	only	-	Apr	10	2:00s	1:00	S
+
+Rule SovietZone	1945	only	-	May	24	2:00	2:00	M # Midsummer
+Rule SovietZone	1945	only	-	Sep	24	3:00	1:00	S
+Rule SovietZone	1945	only	-	Nov	18	2:00s	0	-
+
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	Europe/Berlin	0:53:28 -	LMT	1893 Apr
-			1:00	C-Eur	CE%sT	1945 Apr 2 2:00
+			1:00	C-Eur	CE%sT	1945 May 24 2:00
+			1:00 SovietZone	CE%sT	1946
 			1:00	Germany	CE%sT	1980
 			1:00	EU	CE%sT