Looks like it was a PR Mk1G, there is a better illustration on the second site, which also lists the big canopy bubble and the guns
But the first site implies Cotton was out by the start of the war
Interesting, I had always thought that the defining point of a PR Spit was the huge leading edge tanks in the wings - and thus no guns.
The first site has pretty garbled English ... but the dates are right. Cotton was dumped in mid June 1940, after France but before the BoB developed. Cotton was a pirate ... but he was also responsible for setting up aerial reconnaisance and developing many of the 'modern' methods. It was probably time for him to go, but his regular RAF replacement, Tuttle, held him in very high regard. Cotton essentially broke through, under, over, regular channels and proper procedure and establishing what PR could do. Without Cotton it is unlikely that RAF (= Allied) PR would have developed before late in the war (Cotton built a better mousetrap and customers started queueing, and the RAF had to deliver). But yes, he was a pirate.
The leading edge tanks were for long range variants. The first PR Spits were modified fighters ... with two cameras (Cotton put lead in the tail to simulate a second camera and exposed his deceit after Farnborough were happy with the performance with the one camera they had authorised ... said he was a pirate). Also Cotton introduced stereo analysis using a private contractor he knew (the Luftwaffe never used stereo, just great big beautiful plates). Being Cotton, and getting things done (there was, I believe, a war on), the finances were 'irregular', and the Air Marshalls were sticklers for 'by the book' and financial probity ...