Fourth Army was engaged in the second phase of the German spring offensive in April 1918 (the Battle of the Lys). 46th (Mobile) Bde moved to First Army on 1 May. The Allied Hundred Days Offensive began on 8 August, with First Army attacking at Arras and the Drocourt-Quéant Line in late August and early September. On 2 October, 46th (Mobile) Bde transferred to Fifth Army, which launched its final advance that day, liberating Lille on 17 October ad closing up to the Scheldt. By the Armistice with Germany, Fifth Army was across the Dendre.