Interestingly, looking at pics of AB910 throughout her life with the BBMF she seems to have had the four blade prop and separate stubs for nearly all her career including the BOB film. At least three mishaps, the worst being the runway collision with a T-6 at Bex... took a while to fettle her after that and she was fitted with the Merlin 35 out of the Flight's Mk II (or so it says on a web page I was perusing!).
The Griffon-powered Mk XII and Seafire XV and XVII each had four blades; Kennet Aviation fly a Seafire XVII and "watch this space" as I believe Richard Grace's organisation will be test flying the XII they are currently rebuilding in the not too distant future...
