Updates a single availability date on a temp candidate

A Conflict will be returned if the candidate availability is locked for editing to another user in Infinity.

The Start and End date must be valid e.g Start date can not be after end date

To create availability set the IsAvailable property to True and the UnavailabilityReasonId property to null

To create unavailability set the IsAvailable property to False and the UnavailabilityReasonId to a valid unavailability reason

The UnavailabilityReasonId field must match active reference data from the /Reference/UnavailabilityReasons method