macbook air silicon drive replacement

Received a message when I tried to upgrade to the latest operating system. The message said that my MacBook Air has a known problem with the silicon drive. And that I need to have it replaced.

I understand that Apple will do this for free. But, I have not been able to find out if they can do it at the Genius bar. Or do they have to send it out for repair?

I want it repaired, and would like to upgrade it to a larger size if possible. But I need to know if, and where it will be done.

Problem is that I travel all of the time. And I dont usually have the luxery of being in anyone place long enough to drop it off for an undetermined length of time.

Does anyone know? I have tried contacting the online folks. But this question does not go to the Live people on line.

thanks,