If you ever wan't to get de-banned, re-start your router to create a new IP. Its that simple people, I've had this secret for a long time.
No, it doesn't work that way. You must have a non-static IP. When you reset your IP, if another computer claimed your IP while your connection was down, your ISP assigns you a new one.
I have reset my router many times, and my IP is exactly the same. My ISP provides me a static IP.
This is also why there is a "bug" in RTB, where the game doesn't remember you placed bricks, and you can't edit your old ones.
Subnet ban would stop you from joining, but according to some people (I've never had a chance to use it) it doesn't work.