The delete lock read the special-dates calendar ids out of preferences, which
the sync only rewrites on its next pass. Restore the app's data (or lose the
preferences any other way) while a mirror still exists and the feature is on,
and the lock is off until then: the delete goes through, looks like it worked,
and the next sync puts the calendar back.
The calendar itself carries the durable CAL_SYNC2 marker the editor lock already
trusts, so read the lock off that. It also covers the mirror of a type since
switched off, which the same sync pass deletes on its own.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Jean-Luc Makiola
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