To avoid an enrollment bonus clawback, I understand that the primary user's card (in this case Platinum) must remain open 12 months - does that mean the second year's annual fee must be paid?

We also signed up an authorized user for the Platinum card due to the substantial grocery store and gas station spend bonus in the first six months. But we then may want to cancel this AU card as soon as possible so the AU can remain under 5/24 for his Chase cards. Can the AU card be cancelled after six months, or does that one need to remain open a full year too to avoid a clawback?

Thanks.....