 The second phase would follow immediately . While the remaining four infantry brigades of the 2nd Canadian and 51st British divisions cleared up the isolated German forward defences and the 3rd Canadian and British 49th divisions ( from I Corps ) began subsidiary attacks , to widen the base of salient captured in the first phase , the 4th Canadian Armoured Division and 1st Polish Armoured Division would move up the corridor to Cramesnil and prepare to advance further south . To prepare for their attack , bombers of the US Eighth Air Force would bombard the German reserve positions at Hautmesnil . The ultimate objective was the high ground north of Falaise , 15 mi ( 24 km ) beyond the start line . 
