Your initial question was a little misleading, rather than asking if a continuous cable from the CBT to the ONT can be used ( it can’t ) , all you are really asking is if the CSP can be some distance from where the external cable would ‘hit’ the property wall , and close to where the ONT is required, that’s not an unusual request, and if practical, would be considered by the installer , you would still have a CSP and a second ( internal) optical cable to the ONT from the CSP , but that second cable much shorter given that the CSP is now closer to the ONT location , the installer won’t particularly care it’s the same amount of cabling work.
The potential problem I would foresee with you supplying your own 70m plus of conduit and expecting it to be used, is if you have not provided a draw rope inside this conduit, could a cable be pulled through it without a draw rope ?, also , should your neighbour sharing the driveway you don’t want disturbed, could they benefit from this conduit should they also order FTTP , are your properties connected ( semi detached) or separate detached houses , would another conduit be necessary for them ?
TBH , it’s not really possible to know what the first stage install techs will make of this ( presumably you are a KCI2 install process according to this checker site ) , they may go along with this , or they may refuse and if you don’t agree to the normal installation process they were expecting to provide ,they simply walk away … 70m of excavation, especially if it’s driveway and not soft surface ( like grass ) , I’m surprised there is no contribution required, as that’s probably a £3k expense on its own , what does your address show on this checker
https://www.broadbandchecker.btwholesale.com/#/ADSL/AddressFeatureProduct
