For the cross-channel attack, now postponed to 1944 and codenamed Operation Overlord, the service chiefs wanted 490,000 SOS troops. Devers trimmed this to 375,000, which would be 25 percent of the theater troop strength, a figure that was accepted by the War Department. The most acute shortages in 1943 were of engineer units to build new airbases, hospitals, supply depots and training facilities. As in 1942, Lee was forced to accept partly trained units. In the first four months of 1944, the number of SOS troops in the UK increased from 79,900 to 220,200. Some lessons had been learned from 1942. The New York POE started turning back incorrectly labelled cargo. In the first day this system went into operation, some 14,700 items were returned to the depots.