Hi lordmatt,
Same thing happened to me a while ago, all users had 9 months added. This seemed to be related to when I had changed hosting providers 9 months earlier. But not clear, and no solution available.
I had to restore the site from a recent server backup. It solved the issue.
A full restore would wipe the newest entries in the forum. Not to mention all the activity data between the last backup and now.
Is there any other way to solve this?
Where does the tool look for the last active data? Maybe we could diagnose the fault and create a better solution.
Sorry I have no idea about a technical/code fix for this.
We lost about 12 hours of activity etc. by restoring backup, we decided this was better than waiting for days/weeks for a fix and possibly never getting one.