Yes, the leading edge at the arrow appears to have some sort of patch of colour that crosses the demarcation of the camo. Maybe I wasn't clear with my theory but my thought is that it could be a repair using a rectangular patch of aluminum , either unpainted or with the previously applied paint that has flaked off. I don't think it's a yellow remnant because, as far as I'm aware, the yellow ID stripes were removed in early to mid 1943, long before this particular bird was built. Besides, these were further out, coincident with the inner cannon. Maybe red dope? EDIT: probably not since it's too light.