It will take until November before there is a "stable network" in place to run trains on a new timetable in the north of England, Network Rail has said.
The firm's director of route sponsorship, Patrick Cawley, was asked about the progress of electrification work in the North West at a meeting in Manchester, where train operating firms again explained how the "timetable crisis" had happened in the wake of late-running engineering projects.
Mr Cawley was asked by Jeff Halliwell - the chairman of Transport Focus, the statutory transport users watchdog - when Network Rail would provide a "stable network for these guys to run their trains on".
He replied "very soon", adding: "we have pretty much broken the back of the North West electrification programme."
Mr Cawley outlined some of the engineering challenges his firm has faced and said: "In September we're looking to complete the work and we're looking to enter into service in November - I think it's the 10th. That's when we'll have the infrastructure ready."
He agreed when Mr Halliwell asked him: "So it's going to be November by the time there's a stable network to run trains on?"
Earlier at the Transport Focus board meeting, attended by a range of train user groups, Mr Halliwell said the public wanted answers to a range of questions relating to what he called the "timetable crisis" in recent weeks.
Hundreds of services have been disrupted since schedules were changed on May 20.
David Brown, managing director of Northern - one of the operators worst affected - apologised again at the meeting for the disruption and said his firm was working hard to lift the current interim timetable which was brought in to stop the sudden cancellation of services.
Mr Brown was pressed as he left the meeting about how this deadline could be met given the November date for infrastructure work completion just confirmed by Network Rail.
He said: "For us to reintroduce the trains that we've taken out we don't need any further infrastructure. But, to implement the December timetable, clearly there's significantly more infrastructure that needs concluding well in advance of that."