I can't speak specifically to what would occur under CA law, but in Arizona the child support must continue to be paid to the person currently ordered to receive it. I can't tell from your question whether you are the person who is supposed to receive the support, pay the support or if you are the 17-year-old. The only one of those individuals who really would want the child support situation to change would be the payor. If that is you, consider filing for a modification of the current child support amount immediately so that you can terminate your child support obligation.
I recently handled a similar situation where the kids moved from Mom's house to Dad's and he kept paying support for a few years. When the baby was close to graduating, he filed to terminate and tried to argue that the payments to mother in the past should be credited against his existing arrears. Unfortunately, the judge's hands were tied and, although support was terminated, he still had the arrearage and could not get back the money paid to mom for the past years. The situation may have played out differently in CA so you should speak to a local attorney to see what remedies you have in CA or if you even want to change anything.