Hang in there. It's good to make other arrangements but people have made it in on the first day of classes. I spoke with some people who were accepted after orientation because some people were no shows. If you still want to get in, call and make sure they know you're still interested. Make your presence know. Call once a week. If this is something you want, be persistant. Let them know you are still available to attend in the fall on such short notice. Usually, this late in the game, if there is a spot that opens up it is harder to fill on short notice because peopel already made other arrangements/lost interests/found nice jobs/etc.