Just trying to be clear on the process:
1. You had a multiple track WAV file from your recorder of which you synced only a subset of those? For example, it was a 4 track file but you synced tracks 1+2 only?
2. You now have a .sync subclip that is VA1A2 and you already started edited sequences.
3. You now want to change the original .sync subclips to VA1A2A3A4?
If yes – you need to remake the .sync clips. Sequences will not update automatically with additional tracks, you need to do a replace edit on those events.
When you say AAF, what are you referring to exactly?
Michael