All of the 19 Marine and Navy POWs had been released by 25 April. After final processing and clearance for return to the U.S. the men were flown home, via Hawaii, in three groups that departed 28 April, 30 April, and 4 May. Each was accompanied by a Marine Corps officer. Members of the first contingent of POWs arrived at Travis Air Force Base, California, on 29 April, thereby completing their 7,000-mile journey from Communist prison camps. Another small group of POWs considered possible security risks were airlifted directly from Japan to Valley Forge Hospital, near Philadelphia, for further interviewing. No Marines were among them. With the initial prisoner exchange completed, staffs of the major Far East commands began to prepare for the final return of all POWs. Operation BIG SWITCH would take place after the ceasefire that, hopefully, was not too far away. On the day that Operation LITTLE SWITCH ended, 26 April, plenary truce talks resumed at Panmunjom. The stormy issue of repatriation of prisoners, which had already prolonged the war by more than a year, was still the one major problem preventing final agreement. There was indication, however, that the Communists appeared to be softening on their rigid insistence of forced repatriation. And, on 7 May, the Communists accepted the UN proposal that nonrepatriate prisoners be kept in neutral custody within Korea (rather than being removed to a foreign neutral nation) and offered an eight-point armistice plan. With modifications, this ultimately became the basis for the armistice. While discussions and disagreements continued on this proposal, another real problem developed from a totally different source. Since early in April rumblings had been heard, through the polite ambassadorial circuits, that Syngman Rhee, the aging South Korean president, was dissatisfied with major truce issues. In particular, he was disturbed over the possibility that Korea would not become reunited politically. Further, Rhee gave indication that he might take some kind of action on his own. The Korean leader had advised President Eisenhower that if any armistice was signed that permitted Chinese Communist troops to remain south of the Yalu, with his country divided, he would withdraw ROK military forces from the UN command. Since South Korean troops, backed by American specialized units, presently manned the bulk of the UNC front line, Rhee’s threat to remove them from General Clark’s command presented harrowing possibilities.