After much consternation, I have found a trigger referencing the invalid object. Trigger [Schedule_UpdateExpiration] on ReportServer table Schedule has the offending reference in it. In test, I altered this trigger to reference the correct report server tempdb and now subscriptions appear to be working properly. So far I have found nothing else broken.

Any comments from anyone? If I'm going through this name change - maybe I should use the default names if MS isn't going to support very well anything else.