In reply to a post by godsell4:

Thanks Ribble, Yes I see that a new cable would be great and could solve that problem.

I agree. As they'll be feeding fibre to the DPU, there is obviously opportunity to feed some copper if need be, though it changes the economics somewhat. It might mean that - where spare copper doesn't exist - a PON solution automatically becomes the most economical upgrade.

An aside on the amount of copper needed:
In the G.Fast trials, there is no permission in the ANFP to run G.Fast frequencies on the live BT network. This means they have overlaid new cable just for the trial.

Some of the cable will be to end-users, carrying the new signals. Other cable will be for power.

The network map for the "technical trial" in Norfolk suggested that power was distributed in two types of cable: one labelled "50 pair", and one labelled "10/20 pair".

From that map, there were 4 DPUs that were fed solely by "10/20 pair" cable; 2 DPU's were fed by "50 pair" cable, but had feeds out of them, each to one extra DPU (among the 4 fed by 10/20); 1 DPU fed by two "50 pair" cables, where both the "50 pair" cables continued out again to feed more DPUs.

The distances there were a maximum of around 200m, so losses will have been limited.