On March 31, 1971, Penn Central filed with ICC to discontinue the 600-series trains at the conclusion of their contract with SEPTA on June 30. The state filed suit against Penn Central on April 7 to stop the discontinuance. On April 23, Penn Central filed in District Court to discontinue the regional services. Five days later, the state and the UTU filed an opposing suit, calling the trains a commuter service. On April 30, Judge John P. Fullam ordered Penn Central to continue operating the trains and referred the case to the ICC.