Two possible cases:
- when these files were added, the Plex server machine had an incorrectly set date/time (in the future)
- these items were added during the course of library creation. They have a file date/time stamp which lies in the future.
Both should be fixable by performing the Plex dance with the affected items.
To prevent this from happening in the future,
- do a sanity check on the file date/time stamp of all files you add and change it if necessary
- activate the automatic time synchronization of both the server machine and the file server/NAS
- give your Plex server machine enough time after boot up, to actually perform the time synchronization. i.e. don’t add new files when it’s not booted up completely yet.
