Arthur David Olson <olsona@elsie.nci.nih.gov> writes:
+ If you want two separate transitions + (for example, + a one-hour retreat from + U. S. Eastern Standard Time + to + U. S. Central Standard Time + followed one hour later by a one-hour advance to + U. S. Central Daylight Time), + you can artificially + (and slightly inaccurately) + specify the UTC offset change as occuring a single second too early.
I found that you can do it without the one-second glitch, by coding the transitions by hand, as follows. Zone Hypothetical -5:00 - EST 2006 Apr 2 7:00u -6:00 - CST 2006 Apr 2 8:00u -6:00 1:00 CDT 2006 Apr 2 9:00u -6:00 US C%sT I couldn't figure out any way to do it with just two transitions, which would be the obvious way to do it. (Nor could I do it with wall clock time; I had to resort to UTC.) Admittedly this is kind of kludgy. I suppose zic could make it easier to shoot yourself in the foot, though surely this is low priority.