American Express Membership Rewards - Platinum Amex--when will annual fee for additional authorized users be billed?

Last August I applied for a Platinum card, and the following November I added three authorized users to my account.

When will I be billed the additional annual fee to adding authorized users? Will it be billed along with my primary annual fee, or will it be billed this November?

I'd appreciate any information that anyone can provide. Thanks! :)

I believe it will be charged in November. My experience has been that each card is on its own cycle.

Yep. AU card fees are charged the day you add that card to your account and annually thereafter.