User blog comment:MisterWoodhouse/Uniting the Fandom and Gamepedia login systems/@comment-26231129-20200720203500/@comment-24006128-20200720210628

There is not a way to merge two different accounts after this process, but I've taken this feedback to the team.

Not sure on the exact flow for reclaiming unauthenticated GP accounts after the merge. I'll inquire.