You can convert AAdvantage MC to AAdvantage Visa
For those of you who were forced out, I just got off the phone with Citibank customer service for AAdvantage cardholders. I asked if I could convert my MC account to Visa and they didn't give me a hard time. The only benefit I was going to lose was the first 6 months free. I chose not to switch until after the first 6 months is up.
If you want your AAdvantage Visa card back you can get it back!