 Complete the following phrase:  Following the liberation of the Crimea in late May, 4th Ukrainian Front found itself in a strategic dead-end. In a major redeployment, 2nd Guards and 51st Armies were shifted to the Reserve of the Supreme High Command, and were then railed northwards in anticipation of the coming summer offensives. In late June the 51st Army was assigned to the 1st Baltic Front; at this time the 417th was still in 63rd Corps, where it would remain for the duration. Exploiting into the gap in the German front created by 