Until the modification plan is signed, do we have to abide by the original divorce papers?

My boyfriend and his ex wife are divorced and have a son. In the original divorce agreement, the ex wife had full custody. As of recently, the ex wife was arrested and put in jail. My boyfriend received temporary custody thru DCF and we filled a child custody modification with the courts to give us full custody of the child. We are currently waiting for a judge to sign off on the papers and go to court (the ex wife missed her deadline to reply so it is uncontested). Summer break is over and we still have not heard from the courts. In the original divorce, the child would go back to the mother soon to go back to school.