Robert, I dug into your complete patch and I see you did manage to insert the proper rules for the period from 1864 to 1916. Personally I prefer the inclusion of all the zone changes... even if they don't result in clock changes. But I won't be upset if you want to keep the rules simple! The rules inside your full patch proposal appear to provide the correct UTC offsets. As for your comment that "sources differ": Both sources come from Tammy Hardwick of the Creston Museum. The reason they differ is that Tammy discovered new information after she wrote the first article. She explained that to me in an e-mail. +# It also is not clear whether in the period after standard time was adopted +# (1884) until 1916 whether Creston was PST or MST (-8:00 or -7:00). +# Sources differ. For now we will stick with MST. The transition dates +# are guesses. + # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Vanc 1918 only - Apr 14 2:00 1:00 D -Rule Vanc 1918 only - Oct 31 2:00 0 S +Rule Vanc 1918 only - Oct 27 2:00 0 S Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Vanc 1945 only - Sep 30 2:00 0 S @@ -1813,7 +1892,10 @@ -8:00 Canada P%sT 1947 -8:00 Vanc P%sT 1972 Aug 30 2:00 -7:00 - MST - +Zone America/Creston -7:46:04 - LMT 1884 + -7:00 - MST 1916 Oct 1 + -8:00 - PST 1918 Jun 2 + -7:00 - MST