Deborah Goldsmith <goldsmit@apple.com> writes:
In America/Indiana/Knox, on April 2, 2006:
1:59:59 EST is followed by 1:00:00 CST (because this location switches to Central Time at that moment, and it's Standard Time in that zone) 1:59:59 CST is followed by 3:00:00 CDT (the normal DST transition)
That may be what the letter of the regulation says (I can't get docket OST-2005-22114 from http://dms.dot.gov right now) but if so, the regulation is obviously in error. The intent is that 01:59:59 EST be followed by 02:00:00 CDT. Nobody is going to change their clocks twice in the same morning. Hence on April 2 there will be an extremely unusual one-hour period during which there will be five (instead of the usual four) time zones in the lower 48 states: PST (-0800), MST (-0700), CST (-0600), CDT (-0500, in a few counties of Indiana), and EDT (-0400). I'll draft a proposed change along those lines. It's a bit more complicated than the patch you sent, because America/Indiana/Indianapolis needs to split into two zones. Daviess, Dubois, Knox, Martin, Perry, Pike, and Pulaski counties, which are currently in the America/Indiana/Indianapolis zone, need their own zone now that they are moving to central time which means they now have a new unique time zone history. Starke county already has its own zone America/Indiana/Knox, and that entire zone will move to central time, so it does not need to split. I think the biggest city in the new zone is Vincennes, so the new zone should be called America/Indiana/Vincennes.