You don't want anybody in the band to have played that piece. Reasoning? If this weren't a rule, there are some schools I know of that WOULD repeat HS pieces on a 2 year cycle. I know there were some schools that would give their students the ATSSB etudes years early to have them work on them to death by rote. If your seniors already know the piece because they played it as sophomores, are they really going to get anything out of going through it again, but with the current freshmen and sophomores having to learn it too?
Unless you're in a situation where the program has completely collapsed and any success down to even putting the instrument together right is major then maybe it's okay, but then again, you are probably:
1. Not going to UIL because that's not what the students need.
2. In a situation where playing the same pieces over and over again will bore the kids who don't really care and it will kill it for everybody.
So even then not the best idea.