When discussing 'BT and Cabinets', you all need to remember that the BT cabinet data is quite inaccurate, thought to be often 1km out of actual position and known in one case to be 5km out!
Not only that, but your "line" may not take the most direct route. It's not unknown for a cabinet to be 1 km away from you but the cable length is 3 or 5km. And it ain't just in the sticks either.