Yeah, there is ALWAYS credit for time served--otherwise someone who couldn't afford bail would have to serve more time than someone who could. Ask the SA about how parole or commutation credits work. In NJ, certain crimes have to be served 85 percent without parole, but they tack on a parole term at the end, just to make sure there's continued supervision for a while. Other states have different rules. Commutation or "good time" credit varies widely, too. Just ask, I'm sure they would be glad to explain it to you.