We migrated our old forum to BBpress, we had to add all users, topics and replies via CSV files.
But now all users receive email notifications that they have been mentioned by another user for very old replies, some dating back to the very beginning of our forum in 2004.
I don't know exactly what the trigger is, but I'm guessing that everytime an user signs in for the first time on the new forum, all people who he has mentioned in the past receive an email.
How can I stop this from happening without actually disabling this feature? I still want the users to receive notifications for new replies.
As a way around it I replaced every @ in old messages with @ via query. So the users still see @ but the messages have stopped.