If 'IsTemporaryDeactivated' is set to False via a template, 'DeactivationStart' and 'DeactivationEnd' must be emptied (null). This does not work via the job server. It does work in Object Browser.
This is a product defect (30730).
This will be fixed on a future release of the product. If you require this immediately corrected, please contact Support for a hotfix referencing the defect ID 30730.