@rhill The reason you're seeing this is because the script is pulling the last completed backup date from the SnapshotDates values in com.apple.TimeMachine.plist - which writes those dates in Zulu Time (GMT). Personally, I wish it recorded the value in epoch time. I don't so much want to know when the last completed backup is as how many days have elapsed since the last backup has been completed. Since epoch time is independent of time zone, it makes those calculations much easier. So, like you, I'm left to figure out a conversion to get me the info I need. But that's the why, anyway.