I got banned from gambit on Sunday. I had the game open in windowed mode and was browsing the web while it was matchmaking. When the match was starting, I switched to full screen with alt+enter and got booted from the game for too much fps variance. This happened several times and I was temporarily banned for a while (not sure exact time, maybe an hour or two). Later, I was able to log in and play as long as I stayed in the game the whole time.