tzinfo local-seconds-to-utc offset policy at DST fallback
tzinfo local-seconds-to-utc offset policy at DST fallback Goal: Convert a regional wall-clock time, for example 01:30 on a fall-back date in America/New_York, to a UTC instant using Racket's tzinfo collection. The local-time-to-UTC mapping is not one-to-one around daylight-saving changes. A repeated local time can correspond to two UTC offsets, while a skipp