Your spot on, Fibre to the Cabinet, Copper from the cabinet to you. What he means is that the copper distance from the Cabinet to you is too long, nowt to do with fibre distance .
If you are on VDSL from Cab 9 then at these distances it will be worse than ADSL ( different frequencies - VDSL use highers frequencies that drop off faster over long distance)
What you need to press BT for is a network rearrangement, shifting your copper line to the closer cabinet, or to be put back onto ADSL if they are unwilling to rearrange your line.

Thanks gregormac, understand abit better what has happened now.

Just a thought,
what would happen if you were to order a brand new line, it should get provisioned from the nearest PCP then get VDSL on it, then cancel the old.

Man be a way to get a Stealth rearrange if they are saying nothing can be done.

They generally don't install new lines right to the nearest PCP. There's almost certainly spare pairs somewhere nearby in a multi-pair cable.

The OP's drop wire may already have a spare pair. There's also usually set boundaries that each cabinet covers. It probably does happen, but it will be rare to have a single property with 2 lines from 2 PCP's.

I had though of that in the past, BT are to be in touch tomorrow to see what the next step is and hopefully it's something they look into to see if it's feasible

It would be my guess that any new line would be routed via the same DP as the existing line, and that DP is fed by the same PCP as before.

Spoke to BT again today, offered no explanation and stated I had two options
1: Leave BT and go else where (not a valid option as BT only supplier in area)
2: Go back to ADSL

I said I would like to know what happened and asked would I receive any refund. Was told that as far as they were concerned that although my speed was affected they would only refund for a complete loss of service which they said I hadn't (Not true, phone line was down for around 4 days)

I disagreed and the guy said the matter would have to be escalated to higher team and they would be in touch in 72 hours