All tickets are nonrefundable unfortunately and i don't think you can change the times im sorry.
You can call the Flume directly at: 603-745-8391 and request a change. As of Wednesday 9/30 at 10am, Saturday morning only had 1 ticket available at 9am and the rest of the day was sold out until 3pm.
Not sure as but changing times. You'll probably have to call
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