It shipped with America/Denver hardcoded, taken from what dominates the
historical data on the server. That data is old; the reader has moved.
A zone belongs to whoever is looking at the calendar, and baking one in is
the same mistake as v1's offset-instead-of-zone in miniature -- it looks
right until the reader is somewhere else.
Falls back to UTC rather than to a populated guess: an obviously neutral
wrong answer gets noticed, a plausible one does not.
connor
c197e08af0