Originally Posted by
bgriff
You are looking for this thread:
Amex (USA) restricts bonus based on number of accounts opened/closed (June 2018)
Amex's criteria are different from Chase's and have nothing to do with X/24. More to do with history of opening and closing accounts it seems and with less obvious hard-and-fast rules; that other thread has much more speculation.
But to answer your last question, I have a data point of being able to apply (and getting the bonus) from a mail offer after receiving a "you've had this card before" pop-up during a standard application. I don't know if any data points exist of overcoming the "history of opening/closing" pop-up though. That other thread would probably be the best place to look.
After the rejection from the incognito offer of 50k miles, I logged into my Amex Blue account to see what pre-approved offers I had and to my surprise the same 50k miles/2k spend showed up (it had previously been a 35k offer). I clicked through the application and applied and got an instant approval. I'm not sure why the incognito link didn't work. But I'm guessing that had I received another mail offer, the app would have went through fine.