The purpose of the utc_offset is to stop an event that repeats
And bridges the “week boundary” it’s not returned as the first event.
It won’t modify the start_time of events in the payload itself. You just feed that to a date/time parser/formatter anyway, rather than show it verbatim.
It just stops an event appearing at index 0 that has already occured.
Or conversely ensures an event appears at index 0 which hasn’t occured yet but would be removed per a 0 utc_offset
Usually makes more sense when also feeding in a start_time query parameter.
From the docs:
This is recommended to ensure stream segments are returned for the correct week
TLDR: I don’t think it’s bugged, it’s just not an untitive thing.