[RolandF]

Congrats, David, to your hawkeyes!

So this jet was similarly marked like B3+EK with letters in same size. The position of "B3" can be seen just right of the vertival bar as a dark spot.
The fuselage sides seem to be toned down and the Tailfin was the experimental wooden one. The reason for the damage seems to be at least one well-placed handgrenade in the aft fuselage compartment.

Regards
RolandF