If they are partially used you cannot remove them. You can add your new tickets, but it you don't have a CM prioritize them at entrance, the MB system will use up the oldest tickets. I tried deactivating my old tickets but it didn't matter the system used up the old ticket even though I had my new ticket in hand and swiped it at the entrance I didn't use the magic band. It was quite a mess to figure out. The old tickets were hoppers, the new tickets were base and I didn't need hoppers on my last trip.