Just clicked on Rob's post - it's the same Eric Treacy photo, but clearer in the print version and she's definitely lined out. In the same publication there are a couple more shots of post war pre-nationalisation Stars. 4055, Princess Sophia is pictured in lined green, G - coat of arms- W, with outside steam pipes and looks lined to me, but I wouldn't bet the ranch on it. There is another shot of 4017 (on Dainton Rob, headed for Plymouth, hint hint....) but it's a frontal shot and impossible to tell. I would suggest however, that whatever the justification, there were certainly Star's being turned out from Swindon in full green, lined and branded (yikes) once they started proper overhauls again. They are all wreathed in copious amounts of steam however....
Regards
Alastair M