AA units returning from France were rapidly reinforced, re-equipped where possible, and redeployed for future integration into existing defence plans. 85th HAA Regiment, with 174, 175 and 220 Btys under command, went to
Aberystwyth where it re-equipped with 3.7-inch guns. (On 1 June, AA units equipped with 3.7-inch guns or similar were designated Heavy AA (HAA) to distinguish them from the new Light AA (LAA) units being formed. However, 174 HAA Bty was detached to
South Wales to reinforce
45 AA Bde. On 12 July, Battery HQ and two sections (four guns) went to X site at
Pembrey and the other two sections to T Site at
Sketty on the outskirts of
Swansea. Pembrey was the location of an
RAF Sector Station but the guns were mainly positioned to defend a
Royal Ordnance Factory explosives works. There were low-intensity air attacks on the coastal towns of South Wales throughout the summer, at which the guns sometimes fired without effect, but on the night of 1/2 September there was a heavy bombing raid on Swansea. However, the guns at Sketty were forbidden to fire until midnight because RAF
Night fighters were active. Although T site was by then integrated into a barrage line with
79th (Hertfordshire Yeomanry) HAA Rgt to defend Swansea, the two sections of 174 HAA Bty there were ordered on 11 September to move with their guns and ammunition to London, where the
London Blitz had begun. When they returned a few days later they went to Z site at
Pembroke Dock, and shortly afterwards the rest of the battery moved to Y site (with no guns) at Pembroke Dock. The battery occasionally engaged
Luftwaffe aircraft attempting to drop
Parachute mines in the harbour. In October, 220 HAA Bty was also detached to 45 AA Bde, taking up positions round
Newport, though it had no guns until December, when four static 3.7-inch guns were emplaced. Y site also gained two mobile 3.7s, and the four mobile guns at Z site were joined by a
GL Mk I gun-laying radar set. In November 1940, as the Blitz was intensifying, AA Command carried out a major reorganisation: 5 AA Division's responsibilities were split, with 5 and 45 AA Bdes coming under a new
9 AA Division created to cover the South Midlands and
South Wales. There were few air raids in 5 AA Bde's Gloucester–Hereford area, although the
Gloster Aircraft Company's works at
Brockworth and
Hucclecote were targeted. 45 AA Bde's area, however, was heavily bombed (the
Cardiff Blitz and
Swansea Blitz) and in February 1941 responsibility was split between 45 AA Bde covering Cardiff (including 220 HAA Bty at Newport), and a new
61 AA Bde covering Swansea (including 174 HAA Bty at Pembroke Dock). ==Mid-war==