Timezone changes reported in IATA manual

Paul Eggert eggert at twinsun.com
Sat Mar 29 07:46:02 UTC 1997

Thanks for the IATA updates.  In a companion message I'll propose changes
to the tz tables accordingly.  Here are some thoughts about your comments.

   Date: Wed, 26 Mar 1997 15:55:43 -0500
   From: gwil at mindspring.com (Gwillim Law)

   Chile has changed the end of DST from the second to the third Sunday in
   March, starting in 1998.

Actually, Chile has always switched at 24:00 on the 2nd Saturday of the month.
The previous IATA issues got this wrong for 1998;
the latest issue merely corrected this.

   Cuba has changed the end of DST from Oct Sun>4 to Sun>5 (or more), starting
   in 1997.

This reverts to the rules that Cuba used from 1978 through 1995.
For now, I'll guess that the 1996-10-06 entry is not a typo.

   Georgia has gone on year-round standard time using its former DST offset,
   probably by failing to change the clocks back in October, 1996.

This agrees with an AP story (1996-10-23 13:05-04) quoted by Mathew Englander.

   Israel has changed the end of DST from the third Monday in September to the
   third Sunday in October, starting in 1997.

That news has already been overtaken by events; Ephraim Silverberg
reports that Israel changed the rules again earlier this month.

   Kyrgyzstan has changed the end of DST from the last Sunday in September to
   the last Tuesday in October, starting in 1998.  This may be a typo in the
   manual.  If it said Sep 26 instead of Oct 26, that would be consistent with
   the old rule.  Besides, Tuesday is a rather unusual day for DST to end on.

I'll assume that is a typo.

   Mongolia has changed the end of DST from the fourth Friday in October to
   the fourth Sunday in September, starting in 1997.

Most likely it's the last Sunday in September, the rule from 1985 through 1995.

   Sri Lanka has set its clocks back a half hour.  There's no evidence in the
   manuals as to when this took effect.

Thanks for reporting this.  I used Deja News to find a press release
from the Sri Lanka Media Minister who said that the change occurred at
1996-10-26 00:30 local time.

   Ukraine, except for Symferopol, has changed the time at which DST begins to
   05:00, and the end time to 07:00 (local time).  This is rather unusual, and
   I suspect an error in the manual.

Yes; I'd say the person who prepared those entries wrote down local time,
even though GMT is what's wanted.  That would explain the error.

   (3) In Symferopol, the offset from UTC to standard time is three hours.
   The manual reports that the offset for DST is four hours in 1997, but three
   hours in 1998.  If that were really true, there would be no point in their
   reporting the DST start and end dates for 1998, because DST would be the
   same as standard.

The current tz tables (based partly on earlier IATA issues) has
Simferopol at UTC+03:00, but using unique daylight-saving rules: these
rules are like the EU rules, but they switch at 00:00 UTC instead of
01:00 UTC.  Presumably this is so that the local time of the switch is
the same throughout Ukraine.  It's quite possible that the current tz
tables are incorrect, though.

   Date: 28 Mar 97 01:16:56 EST
   From: Chris Carrier <72157.3334 at CompuServe.COM>

   >(1) Gibraltar has moved its winter time an hour earlier, but not its summer
   >time, so that in the winter it matches the United Kingdom and in the Summer
   >it matches mainland Spain, with a two-hour change each time.

   I actually believe this may not be an error.

Today I checked DHL
<URL:http://www.dhl.com/dhlinfo/country/gibralta.html> and they say
Gibraltar is at UTC+01:00.  I think Gibraltar is still like Madrid
(just as it has been since 1982, according to Shanks).

   I asked for the time in Morocco and was given GMT.

Shanks agrees with this; however, he reports that Ceuta (Spanish
Morocco) is like Madrid, and has been since 1986.

   Would like to ask: is Mexico going to go on DST in 1997 and after?

Mexico started using US-style DST last year; I haven't heard of any
changes since then, so I assume they'll use it this year as well.

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