Also see the full Referral Terms at this page:
https://turbotax.intuit.com/referral/terms/
Note that it says:
"Up to 45 days after an Advocate’s Friend redeems the Offer using the Link from the invitation, the Advocate will be sent an email with Reward information for electronic gift card and charity donation options (if made available). After Reward selection, another email will be sent with gift card e-certificate information..."
