I've asked and got basically a "no". I can believe that if you have a history of spending big $$$ on AWS they get increasingly flexible with raising the limits.

I've asked and got basically a "no". I can believe that if you have a history of spending big $$$ on AWS they get increasingly flexible with raising the limits. But if you don't, they aren't going to let you spin up 500 instances, even if you ask nicely and have a reasonable justification.