Lehmann-Willenbrock left "U-96" in March 1942 to be promoted to "Korvettenkapitän" and appointed commander of the 9th U-boat Flotilla, stationed in Brest. On 2 September 1944 he assumed command of and escaped the besieged Brest just a few days before the town's surrender. He reached Bergen, Norway, on 23 October. In Bergen he was appointed commander of the 11th U-boat Flotilla in December, and held the position until the German surrender in Norway on 9 May 1945.