Why would anyone with half a brain risk having problems, rather than paying for an extension to avoid problems. After all, it doesn't break the bank to get the extension. People trying to skirt the system cause the problems for those of us that live here and obey the laws of the land.
You can go to immigration and they will copy your visa and 90 day due date. Give you a copy and tell you to come in with it if your passport isn't done. That is what I did.