You're screwed.
E-mail them back requesting more information. if you can get a phone number it could be handy as well (its unlikely though).
10k a month and they don't even send a warning! just boot you out! thats sending mixed signals. his spam was okay for awhile but now it isnt and they dont even explain why.
What are the URLs of your sites???
actually they say they disabled it for a number of urls. so at least they didnt kill his whole account.