Nope, they open doors at 1 exactly. No early set ups. I've been birthday partying there 20yrs for my kids, not once did they open at 12:59.
Karen is correct, 12-1 is actually our 20 minute lunch break so most leave to get food.
I am sure the owners wouldn't mind if they are open at that time. I would call them and hour before your party to make sure.
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