With the completion of his third tour Cheshire was officially ineligible for further operational flying. Air Vice Marshal Roderick Carr, Cheshire's former Group Commander when he was at No. 102 Squadron, put much effort into securing Cheshire a promotion to acting group captain, which the Air Ministry finally approved in March. The promotion made Cheshire, at 25, the youngest group captain in the history of the RAF. On 1 April Cheshire returned to Marston Moor, now as the station commander. The airfield was used by the 1652 Heavy Conversion Unit (HCU) to convert pilots from the two engine Whitley and Wellington bombers to the four-engined Handley Page Halifax bomber. Cheshire was in charge of 30 to 40 aircraft and 1,800 to 2,000 men.