Go online at www.six flags.com/guestservices, Going online avoids going to the park for no reason, but if it ain't out of your way then go to guest relations at the entrance of the park after security search between both entrances..
Interesting question. I would imagine there's little you can do especially if you got a deal only for the date on your tickets. Perhaps they might be able to trade them at the entrance and validate them at the ticket office. Good luck, I hope you get what you wanted. :]
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