(c) Crown copyright images reproduced by courtesy of The National Archives, London, UK
Catalog numbers: CAB154 #35001, #35002, #35003, #35004, #35005, #35006, #35012, #35013
British War Office and War Cabinet correspondence from 1943 points to the use of pigeons to drop questionnaires written to fool the Germans and the local population about where subsequent Allied military operations would take place.
This was just one component of Operation Cockade. Here is a link to an explanation of Operation Cockade:
Pigeons had been dropped with questionnaires into occupied Europe by the British since 1941. This was Operation Columba. Residents of occupied Europe sent the pigeons back to Britain with intelligence about the Germans. There is more information about Operation Columba in an earlier post “The Brave Message Writers of Occupied Europe-WW2.”
What you can see from this correspondence is that the questionnaires dropped with the pigeons into certain regions were rewritten as part of the deception plan which was Operation Cockade.
Note above the handwritten reference to the the Special Operations Executive (S.O.E).