well, I am walking around free so, for sure you don't go to prison but you pay a penalty perhaps. In my case I just paid it. It was an honest mistake and they did not bust my chops over it, they did charge interest, which is stupid. But, fine, if your computer can figure it out why not just send me the bill monthly like my city government does?
it's also super easy to setup a payment plan online now if you really mess things up