[SteveB]

Hi

I think the most important evidence is the round shape to the right of the head of the German in the foreground. It can be seen that this is the front end of a large cylinder fixed inside the top of the fuselage. To me that is the variometer which was part of the Type 19 HF radio installation ie before VHF became more standard on Mustangs. I would say likely end 42 to spring 43.

I agree with Nick Beale that the building(s) seem significant there also seems to be dedicated railway access and anti-parachutist/glider protection. The low buildings in the foreground look to me to be original French but the tower in the middle (behind the buildings?) looks German – perhaps an Atlantic wall coast watching structure?

For me the humps and bumps on the skyline are very reminiscent of the Pas de Calais area especially around Boulogne.

Steve