Help, please! So, I ran TM today. After checking for changes, TM told me that I didn't have enough space for a new backup and refused to continue. The partition of the external HDD that I'm using is full nga, but previously it would just warn me that an older backup would be deleted to make space for my new one. In fact, I believe that it actually did some deleting since the current free space (20+GB) is greater than what remained from my last backup. Now, the last time (24 days ago) I backed up was pre-SL. I found this on the Apple Support Forum, which gave me the idea that TM is considering my SL system as a new machine. My HDD isn't with me at the moment (I'm out) so I still have to check if I can access the older backups. So, what are my options? Can I force TM to delete another backup to make room? Do I have to give up on my old backups and reformat the partition? I would really prefer to avoid the last, though.