Subject: [Tzdist] Different view of this ...

From: Lester Caine <[email-masked]>
Date: Wed, 03 Sep 2014 21:48:51 +0100

Zone Test/Test	-3:26:56 -	LMT	1916 Jul 28 # Nuuk
			3:00	XX	X%sT

~~~~~~~~~~~~~~~~~~~~~~~
The key here is that '1916 Jul 28' is the TZSTART time for this zone
and the resulting package has an initial STANDARD event which I now
understand is the 'local time'? But it is more likely that the
transition happened at the UTC/GMT midnight not the 'local' midnight.
In reality we may not actually have a defined time of the transition
which is one of the reasons there can be uncertainty on this material,
but the documents I'm looking at give a date GMT started rather than
date local time ended. So I assume TZSTART would be 19160728T000000Z so
DTSTART is wrong?

I said truncating at 1970 may be better for an initial build - but we do
need to be able to handle this uncertainty. The TZOFFSETFROM:-032656 may
actually an average, or it may ACTUALLY be a a standard LMT time which
was used for the prior time period and for which we as yet have no
documented start date ... so TZSTART should actually be a little earlier
...
~~~~~~~~~~~~~~~~~~~~~~~

BEGIN:VCALENDAR
PRODID:-//CyrusIMAP.org//Cyrus git2.4.17-caldav-beta10+17//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:Test/Test
LAST-MODIFIED:20140903T200017Z
X-LIC-LOCATION:Test/Test
BEGIN:STANDARD
TZOFFSETFROM:-032656
TZOFFSETTO:+0300
TZNAME:XT
DTSTART:19160728T000000
END:STANDARD
END:VTIMEZONE
END:VCALENDAR

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Lester Caine - G8HFL
-----------------------------
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---

From: Lester Caine <[email-masked]>
Date: Wed, 03 Sep 2014 22:08:27 +0100

> Zone Test/Test	-3:26:56 -	LMT	1916 Jul 28 # Nuuk

And I got that wrong ... 19160728T030000Z
( My own documentation is for switch to GMT )