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I unchecked my work calendar in Settings before the weekend, but I still got alarms from it. The widget stopped showing those events immediately, so the setting clearly took effect somewhere — the alarms just did not follow until much later.
Thanks for reporting this — your observation about the widget was the clue. Deselecting a calendar saved the setting but never triggered a resync, so the alarms stayed until the next background refresh. Version 1.14 resyncs immediately when you change your calendar selection.
