I think the way it works is, you're paid after completing the school. You're paid while with your trainer on the road. Which state do you live in? Do you have a felony or misdemeanor? Felony or misdemeanor won't keep you from a trucking career.
Knights is tough. I went through quite a bit of the process only to have my recruiter tell me to kick rocks and get 6 mos of safe driving under my belt and they MIGHT consider me after that. Haven't gotten in any trouble at all in 11 years. This is JMO. Im sure you have something by now but if you havent good luck.