Thread:NoWayThisUsernameIsAlreadyOwnedBySomeone/@comment-24335865-20150509232013/@comment-26143371-20150510180701

I've blocked the IP yesterday. It's limited to one week, but if it turns out to be necessary, I can still re-block it for a longer time span.

I've used something called "rollback". Obviously(I didn't know that before) it doesn't show up there(like most other admin tools).