The Allied defences had been so badly ruptured after the German gas attacks and subsequent advance on the salient that Sir John French, the Commander-in-Chief, believed it necessary to straighten out the line and pull all three Divisions of Plumer's 5th Corps back to a position where they would not be outflanked. The 27th, 28th and 1st Canadian Divisions moved back about two miles to a subsidiary line on the last high ground to the east of Ypres.
Agar wrote to Mabel of his frustrations, "It has now been decided that the new back line of trenches upon which so much work has been done with the object of making them a little better than ditches, has been condemned, as being in the wrong place, and would be nothing but a death trap and could not be held very long against artillery fire coming, as it would do, from both sides....For the last three months the regiments at rest have been building a most magnificent back line of trenches with drains, cement, bomb-proof dugouts and everything that could be devised, including wonderful wire entanglements. The Army for months has been priding itself on this wonderful back line. They now find it is not facing the right way and instead of facing the enemy is almost at the right angle to it. It is things like this that make one very angry and wonder how we are ever going to win the war against so skilled and alert an enemy who leave nothing to chance or luck while we muddle ahead in the same old British way, losing magnificent men of for the want of a little common sense or at least judgement."
Exhausted from twelve continuous days in the Polygon Wood trenches, the Patricias would now be tasked with the difficult operation of withdrawing while still in contact with the enemy. Orders were received on May 3rd to retire to the second line of defence in front of the beautiful town of Hooge, still intact but destined to be in ruins. The new trench system was referred to as the General Headquarters Line (G.H.Q.) and was situated across from the railway line to from Ypres to Frezenberg, running from the eastern edge of Sanctuary Wood past the eastern corner of Bellewaerde Lake. The GHQ Line was well positioned but not constructed with continuous trenches. It comprised a series of well fortified redoubts, each approximately 400 meters apart, connected by thick coils of barbed wire entanglements. A garrison of about 50 soldiers would man each redoubt.
G.H.Q. Line April/May 1915
In preparation for the move every Patricia that was able worked to fortify the new defences. In the late afternoon on May 3rd, the mens' spirits were lifted with the welcome sight of Hamilton Gault arriving back to the battalion, after months of convalescence. He brought with him a small draft of reinforcements and immediately took over supervision of the efforts on Bellewaerde Ridge.
By end of day on May 3rd the incredible undertaking of moving 12,000 men back several miles in complete silence was achieved without a single man killed or wounded. Completely undiscovered by the enemy, the rear guard had successfully outwitted the enemy with regular shots from the front line. The machine guns were the last to retreat to repel any attack that might be thrown at them if the Germans suspected the withdrawal.
There were congratulations all around for a job exceptionally well done. It seemed they night have days to complete their work on the trenches before the Germans would realize they were gone as they were still shelling the abandoned trenches.
At 6:00 am on the 4th, however, the peaceful and sunny daybreak was shattered with the heaviest bombardment the Regiment had yet experienced, knocking their hastily prepared trenches to pieces. Artillery fire rained down on them throughout the day completely unchallenged as their own artillery had not had enough time to set up in their positions. By noon they were running out of ammunition. The Patricias had little choice but to lie at the bottom of the trenches and hope. With support from a company of the Rifle Brigade and a platoon of Shropshires bringing in more ammunition they were finally able to beat back the German assault but the casualty list was appalling. When the Regiment was relieved by the Shropshires at 10:00 pm they had lost 122 men killed or wounded. The worst was yet to come.