American Express Membership Rewards - AU on Platinum

So, I finally got approved for the 100K MR/ 10K spend in 6 months Plat card.. I now need to add my husband as an AU to boost my spending. I know he wont be travelling a lot in the upcoming 3 months - new baby due in June. I am debating whether to get him a Plat or PRG supplimentary card. Two questions

- If we get a PRG card as an AU- willl we get extra MR on grocery/gas when we use his card or will his card get 1X times rewards the same as my Plat?
- At some point later in the year, can we upgrade his card to Platinum card and will I be charged a prorated fees ?
- Will his PRG have the same purchase protection since he is an AU on my card, or do I have to pay with my Plat ?

I am aware of the other benefits of the Plat AU - Global etry/SPG status etc.

Thanks!!

- If we get a PRG card as an AU- willl we get extra MR on grocery/gas when we use his card or will his card get 1X times rewards the same as my Plat?

If you request a supplementary Gold it will not be a Premier Rewards Gold card. It will earn one point per dollar exactly the same as the Platinum card itself.

Thanks Mia. Do you know about prorating fees for supplementary cards ? BTW I got a pleasant surprise when I saw an email for approval this morning. Somehow they reduced the spend to 3K in 3 months instead of 10K in 6 months per my original RSVP code!

Thanks Mia. Do you know about prorating fees for supplementary cards ? BTW I got a pleasant surprise when I saw an email for approval this morning. Somehow they reduced the spend to 3K in 3 months instead of 10K in 6 months per my original RSVP code!

I believe AU gold cards are free under a Plat. For additional Plat cards it is $175 a year for 1-3 card and $175 per card thereafter.(So the best bang for your buck is getting 3, if have 3 family members etc.)

It's $45 for the 1st 5 gold cards under a Platinum account. And like the previous poster said, $175 for the 1st 3 supp Platinum cards.