I have a photo of 205 taken while on the road N316 to Morgny. It is not a close-up, but if I were to guess, it looks like a 40mm roof plate to me. I can see a dark shadow around the turret's top edge, which I interpret to be the raised edge of the thicker roof plate. But it's a tough call.
I can't find anything on a production date for this vehicle. Production of 40mm roof plates started with #250991, starting in March of 1944.