Yes I just realised this too.
In 1944 the aircraft most likely was without the Thimble nose and fin extention. To my knowledge the radar wasn't in use on Coastal Command machines until february 1945.
Having said that I'm sceptical about an RD-serialled Beau in '44. I thought that series wasn't delivered until after new year.
As for markings I'm quite sure the 254 Sqn machines carried Sky or White letters above the wings as long as the invasion stripes were in order - which means they were probably worn until December '44. However, it COULD be that 236- and 254 Sqn's actually carried Red, large letters from August '44, as this aircraft would indicate:
