I've seen people reusing them. I'm almost sure u can.
You have to buy a new one. They change the cups every year so they know whether the cup you have was last years or this years cup.
May have to buy a new one unfortunately. I've tried at Idlewild, who is a partner of Kennywood, and they had me buy a new one. Not sure with Kennywood though.
You will have to buy a 2018 cup to get the deal price. Last year cups are charged full drink price.
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