My first tendency is to keep the account alive as a no AF card and with a lower CL. You will have to keep it for a year before Citi allows that. You could already lower the limit on your oldest card now to cushion the impact of reduced credit on your score. PC requires calling them. If the fee posts before the downgrade is complete it doesn't hurt to tell them about removing it. While the typical rep will offer downgrade to MileUp card you can convert to something actually useful. My first choice would be Dividend. Second is DoubleCash. For TYP ATT Access would be useful. If you keep churning Plats you probably will prefer cancelling them which can be done before the first year is up.