Wow this does seem like a strange error. Never seen it. Probably caused by a managed Distribution list (with a template attached) which may have been deleted. But hard to tell. The easiest way to fix it is to detach all tamplates, be sure to make sure that detaching will remove destination items (edit the template first) and then let it dereplicate, then reattach them. The "fantoms" and blankies would be automatically be removed when they are not being attached in the new version.
After the upgrade, and a sync, do you still have the issue? If so, try the above and if still an issue, please submit this so we can contact you directly and make a recommendation. Sorry for the delay.
http://support.diditbetter.com/support-request.aspx