Confirmed live on 0.16.20 (2026-08-31): one occurrence of a weekly 09:00
series moved to 14:00 comes back with `start` at 14:00 and
`recurrenceId` still at 09:00. The slot the rule made stays put; only the
clock time moves.
The mock set `start` from the slot after merging the override, so it
clobbered any `start` the override carried and a moved occurrence did not
move. Per-occurrence *time* editing - one of the main things the feature
is for - therefore looked broken against the mock and correct against the
server, which is the wrong way round for a mock to be wrong.
It also confirms the choice of handle: `recurrenceId` is the one name for
an instance that survives both a renumbering and a move, which is why the
store re-resolves from it rather than from `start` or a cached id.