the answer is you probably cant.
I suspect there is various areas around the country that have a mess of local cabling where entire pair bundles need replacing, but openreach had a choice to make, either spend what is probably a lot of money to fix, if they did do this it probably would be cheaper to just rollout FTTP, as thats how much I expect fixing would cost. Or ignore it and then be agressive in fending of consumers.
A isp in america had massive floods wreck much of their underground cabling, the state of the even unflooded copper was really bad, cables literally were rotting away and joints held together very fragile that blowing on them would break them apart. The isp simply replaced it all with FTTP as was cheaper than fixing the copper.
BT Infinity 2 Since Dec 2012 - BQM