Steve, I think that you're right about India. The first bike is definitely to India Office specification, with the front mudguard grab handle, upturned silencer and rear wheel protection for the now missing air filter (although one WD contract had that also).
The Indian Army did take some of their equipment to the Middle East though (there are some bikes like this one on 'Thistlegorm' )
The RAF outfit looks quite late. The wing-nut closure on the tool box is post 1941 and I think that it has 4.00 x 18 tyres ?