Mine came last week.
Just to weigh in, I can't imagine the replacement Citi cards will carry over the limit the Amex cards had. This isn't a buyout with one bank buying out another. This is essentially a vendor switch for Costco. Citi will be under no obligation to issue cards with the same spending limit. Everyone will have to qualify and I can't imagine that Amex is going to share information with Citi. I would guess that it is illegal for them to even do so.
I will keep the Amex card if they don't require an annual fee. It was fine when it covered the Costco membership as it was the same cost as a membership. I haven't paid for a CC issuer to make money on every one of my purchases in eons and I don't intend to start doing it again.
I read somewhere today that Amex will lose annual revenue from $80 Billion in charges with the departure of the Costco account. It's almost hard to believe that Costco and Amex couldn't hammer out an agreement.
Its hard to pin a number but that is if they lose all of their CostCo card holders. They will likely retain most of their card holders by offering new accounts. They retained most of the their Canadian card holders when this happened in Canada. Revenue from actual Costco swipes is a fraction of that . Over 70% of the purchases on CostCo Amex's had no relation to CostCo.
Citi is buying the portfolio. Amex owns the accounts, not CostCo. When credit portfolios are sold, the new company usually keeps the credit limits. They will have a lot of opt outs if they reduce credit limits. Buying a credit portfolio is only as good as the number you convince to agree to keep accounts after the transition. Citi's purpose for doing this is to gain more affluent card holders. Those affluent Amex card holders aren't likely to keep their accounts if Citi slashes CLs and raises rates, more so when any of the eleventy billion different visas will work at Costco.
Frankly I'd rather keep an Amex card than a Costco co-branded card with Citi. I already have a Citi card and Citi dicked me over on a long held account that got sold multiple times(HSBC to Cap1 to Citi). They closed my account because they claimed I never gave them my correct address during the transition so they couldn't contact me during the first six months of transition. Not once did they call me. Nor was I notified in any way. When I called them, they had my correct address and correct phone number. Even though they closed my account in error(negatively effecting me) they said nothing could be done because they account was already closed.