The link below indicates an initial 20K for signing up for this platinum card with no annual fee for the first year. I now have a Gold AA MC. As I read the terms and conditions on the new offer it seems to state that "only new customers" for this Platinum card are eligible for the 20K offer. I've never had a Platinum AA MC so am I a new customer even though I've had the Gold card? The "other cards" phrase at the end of that same sentence in the T&C is mystifying to me. I have no idea what it means.

When I signed up for the Gold card 18 months ago I got 12K miles. So it seems to me they ought to give me either 25K or at least 13K new miles for the upgrade. Or should I just cancel the Gold card, wait a bit and apply for the Platinum. Anyone tried/done this and willing to tell me what happened? I could use some advice before I call CS.