Well said Heather, I just did the exact same thing for myself yesterday.
Log into the Busch gardens site with your email and password or with your pass number and zip code. Once you're logged in, you should just need to scroll down until you see the free pass section.
As Heather said. It would be under Pass Member Benefits. Also be sure to reserve your guest, and yourself the date you wish to go. Hope this helps. Wish you well.
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