Okay, so I went and got my Schematic corrupted beyond recognition by an unfortunate part replace option. Also the backup save (DBK) picked up the changes. Now fortunately I only lost about an hour's worth of work as I had changed project name not long before.
However, Capture claims it's got multi-level auto-backup feature. This does not actually seem to work or I'm missing something? I've got it set to 10 minutes, 3 levels, directory .