And here we are a month later and still broken..
1860 Jefferson Tennessee.
Year: 1860; Census Place: , Jefferson, Tennessee; Roll: ; Page: 497; Image: 615.
Result - incorrect/incomplete source citations in FTM and exported GEDs,, then of course any application that imports the GED will also have the problem.
One can only conclude that Ancestry isn't very interested in making sure the basics right.