Finally, in July, it moved to Grimsditch Camp, near Salisbury and joined 100 AA Bde, one of the formations preparing for Operation Overlord, the planned Allied invasion of Normandy.

In February and March it practised air cooperation at Cleethorpes on the Lincolnshire coast and at Easingwold in East Yorkshire, transferring to the command of 105 AA Bde.

The battery was not scheduled to land in Normandy during the early stages of Overlord, so in April its personnel were deployed to Southampton to maintain security around the expeditionary force's marshalling area, while a rear party and the battery's Royal Electrical and Mechanical Engineers (REME) workshop remained at Corsham in Wiltshire to maintain and modify the equipment that it would take overseas.

[23] It was first used to assist the assembly of troops for Operation Greenline on the night of 14/15 July, when the drivers of 15th (Scottish) Division 'found the light a great help to them in finding their way up the pot-holed track through the blinding dust'.

[22] In the subsequent pursuit over Northern France and Belgium, 344 Bty formed part of 106 AA Bde protecting XII Corps as it advanced from the River Somme to Antwerp, with individual Troops widely scattered supporting different formations.

This caused practical problems for the BHQ and REME workshop in supplying carbon rods to individual detachments for the arc lamps and in servicing their searchlight control (SLC) radars.

At the end of November it moved from Weert to Helden, where it resumed an AA role, and then in December went into Corps reserve at Nederweert for rest and maintenance.

[22] On 22 December the battery relieved 356 Bty in the AA role at Geleen and round Maastricht, where there was increased enemy air activity over the Maas bridges in connection with the German Ardennes Offensive.

In preparation for the assault crossing of the Rhine (Operation Plunder) the battery underwent intensive training in movement light and in using the 20 mm Polsten gun, which was replacing the LMGs issued to searchlight detachments for AA defence.

[1][30][31][32] As part of the deception plan for Operation Plunder the searchlight detachments exposed some of their lights every night for at least a week before D-Day to accustom the enemy to their use.

Once the river was crossed, 581 Bty helped to transport fuel to the front line, then sent A Troop to support 6th Airborne Division during its overland advance.

[37] In early April the battery was illuminating bridging on the Weser and then helping 15th (Scottish) Division in its advance, including defending divisional HQ against roving groups of German soldiers.

On 23 April it began deception lighting at Artlenburg in preparation for the assault crossing of the River Elbe by 15th (Scottish) Division (Operation Enterprise).

[37] In May 1945, after the German surrender at Lüneburg Heath, 344 Bty was used to provide illumination over Hamburg, particularly the Prisoner of War (PoW) cages and the bridging operations on the Elbe.