After a pause on this objective of about four and a half hours the London Scottish (168th) and 1st Londons (167th) were to "leapfrog" through the leading troops and carry the Cojeul Switch, the Scottish objectives being Back, Card and Telegraph Hill trenches (north of the Neuville-Vitasse-Wancourt Road). Here a further pause was to be made, after which the third phase of the battle would be taken up by the 167th Brigade, who would advance, covering the whole Divisional frontage on to the Wancourt line (Brown line).
To return to the 1/4th Battalion. The day spent in Achicourt prior to manning battle positions produced the first serious German retaliation to our bombardment. As already remarked Achicourt was "stiff" with batteries and also contained a very extensive and important ammunition dump. Doubtless the Bosche decided that the quickest way to silence our guns was to destroy their supplies of shell, and from 11.30 a.m. until 5 p.m. he bombarded the village, causing a good many casualties in the Battalion and firing several houses which formed part of the dump. The village square, moreover, was packed with lorries loaded with shell waiting to move forward with the batteries, and unluckily the enemy obtained some direct hits on these. For some time the flying fragments rendered the place remarkably unhealthy. Excellent work was done in saving two lorries by Major H. Campbell of the Kensingtons. He well earned his D.S.O. by driving two of the blazing lorries out of the square into a place of safety.
The battle positions occupied that night by the Battalion were as follows:
| A | Company | (Lorden)—New Battery Trench. |
| C | " | (Bowater)—Southend and Margate Trenches. |
| D | " | (Spiers)—Astride the Neuville-Vitasse Road in Battery and New Battery Trenches. |
| Battalion Headquarters—In North End (Circular Work). | ||
| B | Company | (Stanbridge)—Attached as "moppers-up" to the Kensingtons. |
The role of the Battalion was laid down to provide for various eventualities that might arise according to the degree of success achieved by the assaulting battalions, and it was therefore held in readiness either to assist the Rangers in forming a defensive flank in case of failure by the division on the left, or to lend weight to the Scottish attack on the Cojeul Switch.
At 5.30 a.m. on the 9th April, after a hurricane bombardment of the German lines, the British barrage lifted and the attack began. The advance of the 56th Division was deferred until two hours later to allow the 14th Division, whose start-line was less advanced, to come into line, and accordingly at 7.30 a.m. the Rangers and Kensingtons moved to the assault, followed by B Company of the 1/4th Londons who were equipped with Stokes mortar shells for dealing with deep dugouts.
B Company's job in mopping-up proved easier than had been expected, for the German trench garrisons had been confined to their deep dugouts for some days by the intensity of our bombardment, and the resultant difficulties with which they had been faced in getting their rations and water up from the rear made them on the whole not undisposed to surrender; and in a short time the Battalion, in Brigade reserve, was cheered by the sight of bodies of German prisoners marching in fours down the road to Beaurains in a dazed and exhausted condition.
By 9.30 a.m. the Blue line on the whole of the Brigade front was in our hands, and its consolidation was at once put in hand by the assaulting troops with assistance from the 512th Company R.E. and a company of the Cheshire Pioneers. At 11.20 a.m. the Scottish moved forward on a three company front to attack the Cojeul Switch. Their advance was met with heavy machine-gun fire, and although one company succeeded in gaining Back Trench, the furthest of the three lines forming the Cojeul Switch, and in pushing patrols beyond it, the battalion was forced ultimately to fall back to Telegraph Hill Trench, the front line of the Switch System and that nearest to Neuville-Vitasse.
At 12.30 p.m. the 1/4th Londons were ordered to advance to fresh positions on the western edge of Neuville-Vitasse, where they came under the orders of the 167th Brigade. The move was completed by 4 p.m. with A Company in Tree, C in Leaf and D in Pine; B Company (still under the orders of the Kensingtons) having by now withdrawn to reorganise in Deodar Lane after their fight.