[tz] Samoa: Daylight Savings

[Robert Elz]

    Date:        Mon, 10 Sep 2012 11:45:03 +1300
    From:        "Nicky" <pereiranick at mcil.gov.ws>
    Message-ID:  <000101cd8edc$c0599ca0$410cd5e0$@mcil.gov.ws>

  | Can you please update Daylight Savings information for Samoa (South
  | Pacific). Daylight Saving Time commences on Sunday 30th September 2012 and
  | ends on Sunday 7th of April 2013.

Thanks for the update.

  | Please find link below for more information.
  | http://www.mcil.gov.ws/mcil_publications.html

I note that that also includes Summer Time dates for the summer of
2013/4 which look as if they may be following the pattern of summer
time (daylight savings) running from the last Sunday in September to
the first Sunday in April - so I am going to assume that for years
even further into the future in the patch I am submitting below for
consideration.

If you have any reason to believe a different rule is likely to
apply, now, or any time in the future (and/or if there are any
exception years) we'd appreciate learning of it as far in advance
of the change as possible (3 weeks notice is not really enough
preparation time for most users of this data).

kre

The following patch is against the (as yet unannounced) tzdata2012f
release.

--- australasia	2012-08-31 20:27:35.000000000 +0700
+++ australasia.new	2012-09-13 16:03:52.000000000 +0700
@@ -628,6 +628,25 @@
 # Although Samoa has used Daylight Saving Time in the 2010-2011 and 2011-2012
 # seasons, there is not yet any indication that this trend will continue on
 # a regular basis. For now, we have explicitly listed the transitions below.
+#
+# From Nicholas Pereira (2012-09-10):
+# Daylight Saving Time commences on Sunday 30th September 2012 and
+# ends on Sunday 7th of April 2013. 
+#
+# Please find link below for more information.
+# <a href="http://www.mcil.gov.ws/mcil_publications.html">
+# http://www.mcil.gov.ws/mcil_publications.html
+# </a>
+#
+# That publication also includes dates for Summer of 2013/2014
+# which give the impression of a pattern in selecting dates for the
+# future, so for now, we will guess this will continue
+
+# Western Samoa
+# Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
+Rule	WS	2012	max	-	Sep	LastSun	3:00	1	D
+Rule	WS	2013	max	-	Apr	Sun>=1	4:00	0	-
+# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone Pacific/Apia	 12:33:04 -	LMT	1879 Jul  5
 			-11:26:56 -	LMT	1911
 			-11:30	-	SAMT	1950		# Samoa Time
@@ -636,7 +655,7 @@
 			-11:00	-	WST	2011 Sep 24 3:00
 			-11:00	1:00	WSDT	2011 Dec 30
 			 13:00	1:00	WSDT	2012 Apr 1 4:00
-			 13:00	-	WST
+			 13:00	WS	WS%sT	
 
 # Solomon Is
 # excludes Bougainville, for which see Papua New Guinea