So managed to break league.... again. Ivern gave me a negative dodge timer.
So I managed to ban Ivern, and somehow pick him after the banning phase at the same time. I also got a dodge timer, but that's normal. I'm only doing league on my PC at the moment, but I thought riot would like this here as well as in the bug report tool.
Edit: during the typing of this post I start going down in the negatives on my dodge timer. Seems to end after about 40 seconds or so after the normal dodge timer.