The 6th Marines returned to Saipan once Tinian was secured. There, the regiment alternated searching for Japanese holdouts, conducting small unit training, and improving habitability while preparing for Operation Iceberg, the seizure of Okinawa which would serve as the final stepping stone on the long road to Tokyo. The 2nd Marine Division was designated the Tenth Army reserve. In April 1945, elements of the 6th Marines were part of the diversion force at Okinawa but returned to Saipan without actually going ashore. Most of the time at Saipan was devoted to preparation for Operation Downfall, the invasion of Japan. The 6th Marines were slated to land on Kyūshū in the fall of 1945. Fortuitously, that operation was not needed when Japan surrendered in August. The 6th Marines made an administrative landing in Japan for occupation duty in September 1945 and remained there for almost a year before returning stateside.