Would these business contracts not now be swallowed up by EI for the businesses that have a preference of BFS over BHD. EI are now pretty established on BFS - LHR and upping flights to X4 day.
Coming back from Hong Kong in 2002, arrived into LHR earlier than thought and bmi changed our flight into BFS rather than BHD to save us hanging about. Can remember in that instance, only about 15 people on the flight on an A320. Can remember asking the crew on the flight, re the light load, and they basically said this is the norm... Obviously if you worked for BD, you'll be much better versed on the situation.