The failure to upgrade tracks between Bolton and Manchester before May 2018 was blamed for severe disruption faced by passengers across the north, as a new train timetable was unable to run properly without it.
This week the work has been completed but was nine months behind schedule.
The announcement was made by a representative of train operator Northern, at a West Yorkshire Combined Authority (WYCA) meeting on Thursday.
Northern will also run a full timetable this Saturday after long-running strike action was called off.
It will be the first weekend since the end of last summer that the dispute has not affected services. Industrial action was halted by the RMT union last week, but the announcement came too late to adjust last Saturday's timetable.
Speaking at the meeting, Northern's stakeholder manager Pete Myers said the development was "terrific news".
He said: "The strike has ended, or rather it's been suspended is the truth of the matter."
"The impression I'm getting is that we (Northern and the union) are talking again.
"It means we can run a Saturday service again.
"This will actually be the first time we've run this timetable on a Saturday. But I don't say that expecting any horrors - it will run."
The RMT said on February 6 that Northern had guaranteed the jobs of conductors on trains. Uncertainty over their futures had led to the dispute in the first place.
A total of 47 days of strike action have been taken by the union in the last two years over the issue.
The news was welcomed by Wakefield Council's portfolio holder for transport, Matthew Morley.
He told Mr Myers: "I'm really, really, really pleased to see you've come to the negotiating table with the RMT.
"I back the guards, because at the end of the day, this is about safety.
"When you think of the number of Saturdays these people have gone on strike and lost pay as a result, it's incredible.
"I'm pleased to see we're moving in the right direction."