I am now confused. You had a tree that you made a "complete mess of"... where was that tree? On Ancestry, or in FTM.
You took the backup copy of FTM and what did you do with it? You restored it in FTM? And then it continued syncing with ancestry? Or you took your backup copy and restored it FTM and then you took THAT tree and uploaded it to Ancestry?
Or in FTM you restored your backup copy and somehow added it to the original tree?
Could you please outline the steps of exactly what you did, and use the term UPLOAD if it goes from your Computer to Ancestry and DOWNLOAD if it comes from Ancestry to your computer?
Just so we know we are talking about the same thing.