Got the Amex Plat last may when they had the 100k bonus and AF came up end of May...
I called several times before that to see what kind of retention bonus I could get and max I got was 10k (after all the offers of redeeming my points towards AF!
No thank you) Decided I would wait till AF posts and call again.
Called in today (BTW direct number to retention: 1 (800) 452-3945) and spoke to a nice man Kevin who right of the bat gave me the best offer he saw available on my account $150 or 15k after 3k and 5k immediately to keep the card. I asked him about a 30k offer and he said if it was here I would give it to you but thats all it shows me for now.
Interesting things Kevin did tell me was :
1) He could see how many times I called in before to speak to someone about this matter
2) He mentioned that retention offers change very often. He said one time he saw it change from an offer to no offer in a matter of 30 minutes from someone who happened to call in twice and that he has no control over it. I told him I would keep on calling till I get the 30k offer or until my 30 days are up and he seemed fine with it!
Hope at least some of that DP was helpful