"St Austell Bay" remained in the Mediterranean Sea for the next five years, mainly operating in the Aegean and Adriatic, on patrols, guardship duties, and several periods as part of the Haifa Patrol, attempting to intercept ships carrying illegal Jewish immigrants to Palestine.In April 1950 "St Austell Bay" and sister ship exchanged with the Royal New Zealand Navy frigates and , arriving at Auckland on 3 July to join the RNZN 11th Frigate Flotilla for exercises, patrols and visits in the Pacific, finally returning to the flotilla at Malta on 4 January 1951.