I upgraded from 2011 to 2012 today. I thought that when I did this it would create a new 2012 file, and leave the 2011 file untouched.
Instead, it appears to have just converted the 2011 file. After the upgrade, I could find only one .ftm file. I must admit that the dialogue box did clearly state that the file was going to be converted and could not be used in an earlier version of the program.
I did create a backup file as part of the conversion process, and I was able to restore that backup without a problem into FTM 2011.
It's the first time I've upgraded a file like this so I have no first hand experience. From many posts here, I had always thought the upgrade created a new file, but maybe I misinterpreted them (wouldn't be the first time).
Or is conversion, rather than creating a brand new file, new in FTM 2012?