Eighth Army captured Catania on 5 August, and the AA units moved up behind it to defend the airfields. 12th LAA Rgt defended Catania under 73rd AA Bde, with 34 Bty detached to Comiso under 62nd AA Bde. By mid-September, when Eighth Army launched Operation Baytown to cross the Straits of Messina onto mainland Italy, 34 Bty had rejoined RHQ at Catania, while 36 Bty had been pushed forward to Messina. During the early stages of the fighting on the mainland 12th LAA Rgt remained in the area of Messina and Milazzo alongside 61st HAA Rgt under 73rd AA Bde.