 On 9 April, the 183rd Infantry Brigade ceased to exist as a formation and formed HQ Residue Concentration Area to aid the invasion preparation.The 4th Battalion, Northamptonshire Regiment and the 10th Battalion, Worcestershire Regiment were attached to 21st Army Group to aid 185th Camouflage Field Company, Royal Engineers.The men of the 4th Northamptonshire Regiment created 150 fake Landing Craft Tanks (LCTs), made from steel tubing and canvas, and positioned them along the River Deben at Ipswich, as well as at Oulton Broad, Lowestoft and Great Yarmouth.