After the remaining Axis forces evacuated Sicily, Eighth Army regrouped to invade mainland Italy. The opening phase was Operation Baytown, an assault crossing of the Strait of Messina by XIII Corps supported by 2 AA Bde. Brigade HQ began reconnoitring sites to cover the operation on 18 August, the day after Messina fell, and sent forward two batteries of 51st HAA and two of 74th LAA Rgts for the first deployment. 298 HAA Battery of 97th (London Scottish) HAA Rgt also went forward to support XIII Corps in the medium artillery role. The crossing was to be made with a variety of landing craft and these required AA protection as did the assembly and embarkation points and supply dumps. 2 AA Brigade left 298/97 HAA Bty and two LAA batteries, 13/40 and one from 2nd Canadian LAA Rgt, to defend these areas, and embarked with 51st and the rest of 97th HAA Rgts, 53rd and 74th LAA Rgts to deploy on the Italian side.