Thanks for your replies Colin, it's much appreciated.
Why he has been banded may be the result of something that happened in the past. Is he aware of anything that 'happened'?
However, he also has an INP (Impulse Noise Protection) level of 3, which suggests that there may have been noise on the line at some point. Is any audible on the phone?
No, nothing has happened out of the ordinary and there is no noise on the line at all. To be honest, I was a telephone engineer (cable jointer) on BT for 20 years before a back injury led to medical retirement, and I recently asked an old colleague of mine to do a line test for me - all came back clean and clear, with no battery contacts, no earths etc., etc., just a perfect (for telephony at least) line.
I'm not sure of actual line length from the fibre cab but again, my mate is going to look at the cabling records to get line length for me, and as soon as I know I'll let you know too - unfortunately, time is the problem as I go away on Tuesday so it may be a while before I can get that info to you.
What puzzles my (very) untrained eye is the bitloading graph, as there is nothing over Tone 1950 - does that not indicate that half of the bandwidth is not being used and therefore he never will get more than half speed? Or have I got it completely and utterly wrong?
Thanks again for your help.
EDIT: Doh! I think I've just realised about the bitloading graph - that's what you mean by banding isn't it? They've capped him at that rate so he never will achieve any higher speed until the cap comes off or they move him into a higher band. I just want to point out that I'm not thick, I just had to finish before broadband came along