To be honest, I wouldn't necessarily trust what Citi customer service relayed to you in the message. The only way to confirm that your fee has been waived is when it shows up on your statement. Even if the fee is waived, it will appear as a line item, with a $0. Mine for this year appeared as follows:
MEMBERSHIP FEE MAR 15-FEB 16 $ 0.00
Note that I originally applied for my card and received it during the month of February.
I did a switch over from AT&T card (no bonus given) and got this:
4/16 MEMBERSHIP FEE LESS $450._____WAIVED $0.00