On
UK Serials I just found a real puzzle. It gives WB802 as type "HP.39 Messenger" without any further details; the same is given by
RAFCommands ? The meeting place for RAF researchers (who probably took their data from UK Serials!). It can't be Handley Page HP.39 as that was the Gugnunc and it doesn't seem to be any sort of Miles Messenger (according to the Putnam Miles book).
Google doesn't help as you get some Hewlett Packard device called a Messenger, so does anyone have any idea of what that was (or was intended to be)?