You can. As long as there are tickets available they’ll do it for you.I think you should be OK for the Monday even though it is a holiday. The party is busiest on Friday nights with the locals going to those. Plus not everyone gets off Columbus day and the next day is a work day. I don't think that you would be able to switch since they are non refundable and non transferable. I think you are pretty much stuck with what you buy. I would keep the Monday anyway.
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