Sounds like negotiation, I've not had the email, but it seems to be an actual thing. I checked and each of my four CCs is, of course, Visa. I don't want another CC, it's not like I need the ones I have. I think you can use Apple Pay, not sure how that works if it's still tied to a Visa card. A bit of a stupid move if Amazon stick to their guns and Visa don't budge.
I hate Amazon, but it's perilously convenient. Though I'm, in general, trying to buy less stuff.
ETA: you have mail. Oh well, I'm not about to get another CC unless my wife has a MasterCard.