Wanklyn was ordered to depart again on 30 June 1941 to patrol the southern Straits of Messina. Within twenty-four hours he had spotted a liner. "Upholder" closed to very close range and fired three torpedoes, but the skilful seamanship of the Italian captain avoided the torpedoes by zig-zagging. Wanklyn concluded that the torpedoes had probably passed under the ship. The next two days were spent avoiding two destroyers, which were clearing a way for an oncoming convoy. On 3 July, Wanklyn's patience was rewarded when a 4,000-ton tanker hove into view. He pursued it as it hugged the coastline but was forced to break off as it changed course around Capo dell'Armi. While in the vicinity of Cape Spartivento, three hours later, he spotted three ships escorted by one destroyer. The escort suddenly dropped a depth charge and turned straight towards "Upholder". Wanklyn dived the submarine to 45 feet and climbed to periscope depth when he could hear the destroyer passing off to the west. He engaged a grey cargo vessel laden with wooden packing cases. Two explosions were heard and distress signals identified her as "Laura C". The destroyer dropped 19 depth charges, which shattered light bulbs and came close to damaging the submarine. Later, a submarine chaser dropped 27 depth charges wide of the target. "Upholder" withdrew to Malta on the 8 July.