This grainy image from wartime footage shows Churchill at Oakington in 1942. The Stirling taxiing in the background has a 7 Squadron identification code of MG.
7 Squadron joined the PFF in August 1942, and flew Stirlings until re-equipped with Lancasters in July 1943.
Although we have not yet confirmed that 7 Squadron was in the PFF when this footage was taken, it would seem highly likely that Churchill, who was very much a hands-on leader, would have visited the new Pathfinder bases, including Oakington.
With thanks to Dave Cheetham for the information about the aircraft in the background.