Hi,
your screen shot is not from the Internal Database View but from a certain medium under Devices & Media. In this view, DP displays exactly the remaining protection for the given objects on the given medium, so you can see when they expire and which object may keep a certain medium from expiring. So that view is correct provided you looked into a medium that was written approximately a week before taking this screen shot.
As to an object with Permanent protection suddenly going None or Expired, that shouldn't happen without manual interaction (explicitely recycling the medium or at least unprotecting the given object).
HTH,
Andre.