I had imagined this was taken soon after call-up but subsequently noticed the shoulder cord. This may signify he had been promoted to Bombadier (although Corporal chevrons which would normally accompany them not visible), so after training and maybe not long before embarkation for France.

Seated with some mates, they now have greatcoats - distinction between forage caps and peaked caps not known.

Captioned by Harry as 'Dourges 1940', Dourges is in northern France not far from Dunkirk. Harry was based there for a while during the 'phoney war' period in early 1940. Harry is bottom right, with Frank Barber upper right.

The reverse in Harry's handwriting. Dave Dolin (or Dollin) also seems to have been a POW in Germany with Harry as the back of another photograph (of a family wedding probably kept by Harry through the war) contains his name and address (Fulham, London) amongst others, all written in different hands.
It also has an official 'Oflag III C' camp stamp. Oflag III C at Lubben seems to have replaced Oflag 78 at Hohenfels then became Stalag III-C where Harry was from January 1943 to May 1945.

Another photograph of the same group, Harry and Frank in much the same positions. This clearly shows Harry's Corporal chevrons.

The reverse. We found this one first and I jumped to the conclusion that it had been taken in Poland where Harry was first sent as a POW. However the translation has been given as: "Do you remember me, sir
I was in the English army in 1940
my name is HARY MUNN"
So I'm wondering now whether the writing was done much later, perhaps at a reunion with non-English speaking Polish people present, and Harry had got someone to write that down so he could show it to them when looking for people he might have met whilst in camp.