If it is fire CAT or ground crew issue, or the airspace issue, then switch the route to the DO328 and BE could use their D8 somewhere else.
They could retime the AMS flight to fit in between the STN flights.
Whatever the issue is, it's not been a problem for nearly 6 months and wasn't an issue when the route was being planned. Airspace wasn't an issue when the F50 or ATR used to fly in to DND, nor was it a problem when BE used to offer BHD and BHX as well as the flights to LCY. Adding one extra flight a day should not be an issue for light aircraft in the area, surely?