Hi, guys.
I have checked the enhanced photo posted by Steffen on December 23rd, and I do not feel we can rule out the possibility that the last letter is a P.
Look at the light upper part of the long vertical line of this letter, an see the hint of a similar shade just outside of the tailband. The curvature of the fuselage would in my opinion make an effect like this possible.
So we have:
?? + GP
or
?? + GF
Looking at these photos again and again, the eyes seems to play serious tricks with You....
If I should make a 'first' id on this kennzeichen now, I would say it was GL+GP....
Damn.... no one have a better photo of this one
Regards,
Andreas