Following the Armistice of 22 June 1940, combat operation concluded on 25 June. On 27 June, II. "Gruppe" was ordered to Beaumont-le-Roger, patrolling the English Channel and participated in the occupation of Guernsey on 1 July. Schnell claimed his first aerial victory during the Battle of Britain on 29 July when he shot down a Bristol Blenheim bomber northwest of Le Havre. On 7 November, off the Isle of Wight, as operations were slowing down and recently commissioned as a "Leutnant" (on 1 November), he claimed his 20th aerial victory. For this feat he was awarded the Knight's Cross of the Iron Cross () on 9 November.