Google Calendar Recurring Event Changes Revert After Sync

When you make changes to a recurring event synced from Google Calendar in BusyCal—such as deleting a single occurrence or declining an invitation—the change may revert back to its original state after the next sync cycle.

Symptoms

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• Deleted occurrences of recurring events reappear after sync
• Declined single occurrences of a recurring meeting invitation shows as accepted again

note

This issue only affects recurring events from Google Calendar accounts. Single (non-recurring) events and events from other calendar services (iCloud, Exchange, etc.) are not affected by this bug.

Current Status

This is a known bug in Google's CalDAV implementation that affects how recurring event modifications are handled. We have reported this issue to Google, but there is currently no fix available from their end. There are several issues with how Google Calendar implements recurring events via CalDAV:

https://issuetracker.google.com/issues/422950689 https://issuetracker.google.com/issues/370546361 https://issuetracker.google.com/issues/65026413

Workaround

Until Google addresses this issue, the only reliable workaround is to make changes to recurring events directly through the Google Calendar web interface:

1. Open your web browser and go to calendar.google.com
2. Find the recurring event you need to modify
3. Make your changes (delete occurrence, decline invitation, etc.) directly in Google Calendar
4. The changes will then sync properly to BusyCal

Affected Operations

The following operations on recurring Google Calendar events may be affected:

• Deleting a single occurrence of a recurring event
• Declining or accepting individual occurrences of recurring meeting invitations
• Modifying details of a single occurrence (time, location, etc.)
• Changing reminders for specific occurrences