Yes it's open and you can make online reservation.. better to go early if you want to take as many rides as possible.. also i would say try to make flash reservations so that you don't have to wait in the long queues and can enjoy to the maximum!
They are open but you need to make a reservation! I just went last week and only got to go on two rides🤦🏽♀️ hardly got to go on the second one
You need to get reservations using https://www.sixflags.com/reserve before coming. You can not buy and use ticket from ticket window. You must do reservation before reaching there.
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