Morning Alan
Not populating AC6A79 (N9) which seems to be TC-AYB miscoding (according to Airframes).
N9 is reserved to FAA NATL Flight Program Oversight Office, so that and the altitude of 4980 seems that it's a miscode.
TC-AYB is allocated 4B8722.
TC-AYB, Diamond DA-20-C1 Katana, c/n C0150, Ayjet Flight School
Nikas