Can't remember the company that operated the aircraft callsign was Prestige. The equipment was Navajos. started three rotations a day but then went down to two. Sometimes the rotations were doubled up either with another Navajo or a Cessna 404. I think they were operating for Hutchinson Telecom. They operated for months if not years, not really sure.
Filton as far as I know, aren't allowed schedule services.