New POST /v1/calendar/events/{event_id}/share and DELETE /v1/calendar/events/{event_id}/share/{user_id} endpoints added for sharing a calendar event with a user and for revoking that share
Absence adjustments now carry a status, which is required when creating one via POST /v1/calendar/absence/users/{user_id}/adjustments and is always returned by the adjustment read, list, create, and update endpoints; an optional type field was added alongside it (breaking)
New optional include_busy parameter added to GET /v1/calendar/absence/users, GET /v1/calendar/absence/users/{user_id}, POST /v1/calendar/absence:search, and POST /v1/calendar/absence:search-now, including busy time from users' calendars in the returned intervals