If it’s a New Build you’re supposed to contact Openreach prior to the Build starting so the infrastructure can be put in place.
As you’ve now built them it’s a bit to late and when people move in they’ll just have to place an Order with their chosen CP who will then arrange for Openreach to come and install them and if there’s any additional Network Construction that needs paying for the person(s) ordering the lines will have to pay the additional cost if it goes over the USO costs.
