"Ellyson" sailed from Portland Harbour on 29 June 1944, to invade southern France on 15 August. She led the destroyer fires support group in directly behind the minesweepers and knocked out defenses for the incoming troops. On patrol on 27 August she illuminated a suspicious fishing vessel and captured it, finding 50 German submariners trying to escape. "Ellyson" remained on patrol to cover the landing of reinforcements and support the invasion until October, then sailed for Boston, arriving 8 November to begin conversion to a high-speed minesweeper. She was reclassified to hull classification symbol DMS-19 on 15 November 1944.