Member for Northern Victoria Jaclyn Symes said V/Line crews would work through the night to replace more than 31000 wooden sleepers on the Melbourne-bound track between Seymour and Donnybrook as part of a $9million upgrade.
Trains need to run at slower speeds over freshly-laid sleepers to allow the track to bed down. To allow for the extra journey time, a temporary timetable will be put in place from July 10.
The small change will allow for trains to fit in seamlessly with metropolitan services on the Craigieburn line as per the current schedule.
Seymour and Shepparton trains heading towards Melbourne will depart four minutes earlier than the current schedule from all stations between Shepparton, Seymour and Donnybrook.
They will run to the current timetable between Craigieburn and Melbourne.
The adjusted times will be in place until further advised. Passengers are encouraged to plan their journey in advance and arrive in time for the train as was published in the timetable.
Passengers can plan their journey by downloading the temporary timetable from the V/Line website or visit their nearest staffed station or ticket agent for a printed copy.
Trains to and from Albury and scheduled coach services will continue to operate as normal.
To allow crews to safely complete sleeper replacement works, some late-night Seymour trains will be replaced with coaches on select evenings.
Specific service change information is available on the V/Line website and will be updated as works continue.