ATC flight data processing system requirement. Traffic to destination EDFX / EDXW can only plan via waypoints YEFAW, UGLOM, DIRBO, SUQIF if the route also contains waypoint EXNEL. This combination of waypoints triggers a special FPL treatment in ATC systems that is required when military training areas EDR201D / EDR201E are active. Since the ATC system does not have information on the MTA status, the special treatment is applied at all times which is unnecessary and inefficient when the MTAs are not active.
When EDR201D / EDR201E are not active, there are other and more efficient route options available via MUAC FRA which bypass YEFAW, UGLOM, DIRBO, SUQIF. Recommended routes avoiding the three points are:
1) BASUM DCT ABFAD DCT OLDIP
2) (ELNAT, TOLGI) DCT ELSOB Y348 OMWEG DCT BADOS DCT OLDIP
3) ABGUS DCT ELSOB Y348 OMWEG DCT BADOS DCT OLDIP
4) SOMVA DCT MAVAS DCT ANDIK N873 HUNQI DCT ROCZO and then OLDIP
5) ADUTO N873 VICOT DCT JUIST HUNQI DCT ROCZO and then OLDIP