From April 1938 most Spits had one wing underside painted black (port) and the other white (starboard) whilst the fuselage was left aluminium. This was so AA-crews would know she was friendly (those Mr. Magoos needed all the help they could get!).
Some had a half-black/half-white scheme for the whole of the underside (inc. fuselage) with the ailerons in the opposite colour as well.
By June 1940 this paintjob was gone
