Good to know I didn't miss it because I wasn't paying attention.
Churchill has been fretting about those mystery structures around Pas-de-Calais for several months now.
We've been reading of heavy allied air attacks around Calais, are these V-weapons part of the Atlantic Wall?
They knew about the construction of the launch sites in northern France by July 43 but were still speculating on their purpose. By September they figured out the Germans were developing long-range rockets and pilotless aircraft. By December 43 they had put it together and determined the sites in France were probably launch sites for both pilotless aircraft and rockets. In the early months of 44 they bombed the sites when they identified them.