Online or in person
Sometimes you are offered upgrades through app but only after about 6 months.
Go to sixflags.com or member services
$12 and get an upgrade in that way you don't have to wait in line you don't have to pay for parking
When you go into the gate
You can upgrade at member services on site.
Getting membership
Go online, tickets, then choose what you want to upgrade
What are you trying to upgrade ?
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