I agree with everyone else. Three are no refunds as far as I know know, but depending how much the upgrade is, you might be able to get away with it.
It doesnt hurt to try but I dont think so. Why not advertise on Let Go or something and sell 2nd ticket? I would call the box office first though to be sure.
Most likely they donate the other tucket
Most likely not, but the box office is your best option!
You should call the box office to get it sorted out.
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