LHI daylight savings (fwd)
Jesper Nørgaard
jnorgard at Prodigy.Net.mx
Sat Nov 4 00:32:25 UTC 2000
James Lonergan's confirmation that LHI always advanced clocks going into DST at 2:00 local time, refutes the idea that Sydney and LHI has always been in sync, apart from the half hour difference while not in DST. I guess I overinterpreted James Lonergan, and apologize for that. I should have asked him instead (I thought I did, but couldn't find the mail, so I probably didn't).
I agree that the patch should be rolled back. We should document history in the time zone area, not invent it :)
Seen in retrospect, this was probably not a very good guess either. Only EEC (the western part of Europe) has notably made a system where all the countries are going in and out of DST the exact same second (in GMT) while not even USA is doing that, much less Canada, Russia or even Australia (from which Lord Howe Island belongs).
Regards,
Jesper Nørgaard
Email: jnorgard at Prodigy.Net.mx
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----------
From: David Keegel[SMTP:djk at cyber.com.au]
Sent: Martes 24 de Octubre de 2000 19.47
To: tz at elsie.nci.nih.gov
Subject: Re: LHI daylight savings (fwd)
I wrote to James Lonergan to clarify the situation about what time DST
starts on Lord Howe Island exactly.
----- Forwarded message from James Lonergan -----
From: "James Lonergan" <kingfish at bigpond.com>
To: "David Keegel" <djk at cyber.com.au>
Subject: Re: LHI daylight savings
My apologies for not responding earlier...I have been on leave.
Lord Howe Island advances clocks by 30 minutes during DST in NSW and retards
clocks by 30 minutes when DST finishes. Since DST was most recently
introduced in NSW, the "changeover" time on the Island has been 02:00 as
shown on clocks on LHI. I guess this means that for 30 minutes at the start
of DST, LHI is actually 1 hour ahead of the rest of NSW.
Regards
Jim Lonergan
----- End of forwarded message from James Lonergan -----
So could we please back-out the following patch:
===================================================================
RCS file: RCS/australasia,v
retrieving revision 2000.6
retrieving revision 2000.6.0.1
diff -pu -r2000.6 -r2000.6.0.1
--- australasia 2000/08/10 13:31:51 2000.6
+++ australasia 2000/10/03 06:01:09 2000.6.0.1
@@ -153,14 +153,14 @@ Zone Australia/Broken_Hill 9:25:48 - LMT
# Rule NAME FROM TO TYPE IN ON AT SAVE
LETTER/S
Rule LH 1981 1984 - Oct lastSun 2:00s 1:00 -
Rule LH 1982 1985 - Mar Sun>=1 2:00s 0 -
-Rule LH 1985 only - Oct lastSun 2:00s 0:30 -
-Rule LH 1986 1989 - Mar Sun>=15 2:00s 0 -
-Rule LH 1986 only - Oct 19 2:00s 0:30 -
-Rule LH 1987 1999 - Oct lastSun 2:00s 0:30 -
-Rule LH 1990 1995 - Mar Sun>=1 2:00s 0 -
-Rule LH 1996 max - Mar lastSun 2:00s 0 -
-Rule LH 2000 only - Aug lastSun 2:00s 0:30 -
-Rule LH 2001 max - Oct lastSun 2:00s 0:30 -
+Rule LH 1985 only - Oct lastSun 2:30s 0:30 -
+Rule LH 1986 1989 - Mar Sun>=15 2:30s 0 -
+Rule LH 1986 only - Oct 19 2:30s 0:30 -
+Rule LH 1987 1999 - Oct lastSun 2:30s 0:30 -
+Rule LH 1990 1995 - Mar Sun>=1 2:30s 0 -
+Rule LH 1996 max - Mar lastSun 2:30s 0 -
+Rule LH 2000 only - Aug lastSun 2:30s 0:30 -
+Rule LH 2001 max - Oct lastSun 2:30s 0:30 -
Zone Australia/Lord_Howe 10:36:20 - LMT 1895 Feb
10:00 - EST 1981 Mar
10:30 LH LHST
-# From Paul Eggert (2000-01-31):
-# For Lord Howe we use Shanks through 1989, and Lonergan thereafter.
+# From Jesper Norgaard <jnorgard at Prodigy.net.mx> (2000-09-04):
+# James Lonergan said that the island always tries to stay in sync
+# with the rest of NSW at all time except for the fact that they stay
+# ahead half an hour when DST is not observed. If this is interpreted
+# literally, they should change clocks at the exact moment that
+# e.g. Canberra changes from normal to daylight saving and vice versa.
+
+# From Paul Eggert (2000-10-02):
+# For Lord Howe we use Shanks through 1989, and Lonergan thereafter,
+# However, as per Norgaard we modify Shanks by assuming 02:30s switchover
+# for half-hour DST.
__________________________________________________________________________
David Keegel <djk at cyber.com.au> URL: http://www.cyber.com.au/users/djk/
Cybersource P/L: Unix Systems Administration and TCP/IP network management
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