On Tue 2018-02-20T15:41:05-0800 Paul Eggert hath writ:
As Guy Harris wrote, the whole idea of TZ='US/Eastern' is reasonably fuzzy and there's certainly no expectation of a particular time zone history for it.
I think a US lawyer would disagree that there is any fuzziness for the "time zone" US/Eastern *if* that were defined as in 15USC260 thru 15USC263. The Uniform Time Act of 1966 https://www.gpo.gov/fdsys/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf was passed 1966-04-13 and specified that all local times in the US were to be set forward on last Sunday April and back on last Sunday October. That was in effect at the tz cutoff of 1970-01-01 and though the spring/fall dates have subsequently changed there is never any ambiguity about the meaning in the US. The fuzziness arises because US/Eastern is a "tz region" as defined by tzdb, not a "time zone" as defined by US law. -- Steve Allen <sla@ucolick.org> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m