Ever since updating to 10.12.5 I've had a strange issue with Time Machine. The "latest backup" shown is not actually the latest backup but the one before that. A reboot fixes it for maybe a couple of days, then it's back to showing the penultimate backup as the latest one.
If I actually enter time machine, everything looks OK and I can restore items from the latest backup, so it looks to be just an issue with reporting the latest backup time in Time Machine preferences and menu bar.
If I actually enter time machine, everything looks OK and I can restore items from the latest backup, so it looks to be just an issue with reporting the latest backup time in Time Machine preferences and menu bar.