I had one season where we were not able to leave our table up. We had black tape along the North or South edge (I forgot which) as well as on the east and west sides. Then when we put the board on its side to put it away, we put the tape side towards the top, so that the mat was hanging down from the tape. There was a black border on that mat, and we used black tape right on the edge so that is didn't create new lines to confused the robot. We also only bothered to place the models on the map that were relevant for the missions we were working on.
It seemed to work well enough for us.