The idea of the plex dance is to remove all traces of the media having been added in the first place, so yes, everything will be deleted. It will be added as if it was never added to begin with.
Plex dance is for worst case. You should just scan library + refresh metadata + analyze library. That catches almost all changes to the files. But if the added date is wrong, it probably won’t fix that. If you know what you’re doing, stop plex and open the database. Make sure you have a backup.
My question is, what do you mean future dates? As in the “date_added” is wrong? Was the system date wrong when you added those files? Because I’ve never heard of Plex using the file’s “creation_date” or any date on the file as its added date.
