After TM reduces the backups to the monthly backups only, what data is stored on it? Is it all data compiled from the daily backups for the entire month? How does TM treat the monthly backup? The reason I ask is, If I add 100 digital pictures per day for a month, are there going to be all 3000 pictures on the monthly backup file after 30 days, or does TM actually delete some of it's backups before the disc is full? If it does, I'm struggling to see a huge benefit of it.