Pictures of RAF Expeditors are pretty rare – there is a well used photo of an HB serialed aircraft in camouflage in SEAC markings, but the underside colour is a slight mystery – by the current APs of the time it should have been yellow undersides, but SEAC had their own rules for somethings.

I doubt sky blue, and wonder is it was actually Sky or Medium Sea Grey.

Later RAF ones flew in natural metal with SEAC roundels.

RN wartime Expeditors were in Temperate Sea Scheme of Extra dark Sea Grey and Dark Slate grey over Yellow undersides. Some had yellow outlined serials. Post war they were natural metal or dark blue