Well if he's going to be that sincere, then I'd unban him and see how he goes.
PS: How does the map rotation work these days?
Not a question of sincerity, it's easy for those kinds of people to flip back to raging and trolling, then back to claiming they've matured after that. If anything I'd reduce the ban to a year, or at least a few more months. Need a ban menu that lets you put in months and years.
Last time I checked, map rotation works by a basic FPTP voting system. At the end of the week, the votes are tallied, then we change to a random map. Then it changes again a couple days later, then it clears all the bricks and leaves everyone stuck in camera mode, then we have bubbleshot wars on an empty plate for a bit, and finally someone comes in and sets it to whatever.