Staff needed for the opening of the Metro Tunnel are not being replaced across the network, putting workers and public safety at risk, the public transport union has warned.

The Rail, Tram and Bus Union has lodged a dispute in the Fair Work Commission over a new roster that the union says would reduce staffing numbers at Flinders Street Station. Metro Trains was due to implement the roster from this Sunday.

The union is seeking further consultation over the changes and alleges dozens of employees could be relocated from the busy hub.

The dispute is part of a broader fight that has frustrated the union ahead of the $15.5 billion Metro Tunnel opening in December.

As the deadline for a “soft launch” with a limited timetable for the tunnel approaches, the union argues that Metro Trains has not delivered the additional employees needed for extra services and to staff the five new underground stations set to open in December.

Instead, the union says, members are being moved from other parts of the Melbourne network, creating workforce shortages all over the city that are not being addressed.

Rail, Tram and Bus Union state secretary Vik Sharma said the union believed there were 100 to 150 vacancies across the network, but these numbers have not been confirmed by Metro Trains.

“Despite the RTBU having flagged issues with safety and staffing over many months, Metro continues to blatantly put corporate profits ahead of Victorians,” he said.

“Staffing numbers advertised have simply not materialised yet. New tunnel jobs have predominantly been moved from the existing network without backfilling the vacancies created.”

Sharma said the government did not have powers in its contract with Metro to force the these vacancies to be filled.

“It is panic stations for Metro. With staffing shortfalls, they are now seeking to force through new rosters that further strip back staffing levels, putting staff and public safety at risk,” he said.

Sharma said resolving Flinders Street Station rosters was key to enabling working rosters for the Metro Tunnel.

In a letter to members, he accused Metro of trying to remove “dozens of good rail jobs” from the station’s operations under the guise of a roster change.

A Metro spokesperson said: “There are no redundancies. The new roster takes effect on Sunday, and Metro will continue making adjustments to ensure staffing requirements are met at Flinders Street Station and other locations.”

A state government spokesperson said: “When the Metro Tunnel opens in early December with hundreds of weekly services, all stations will be staffed appropriately.”

The state government last week announced passengers would be able to travel through the Metro Tunnel from December, starting with a limited timetable, when 30 off-peak services will run each weekday. A full timetable is set to run from February 1.

An official December start date will be confirmed once the national rail safety regulator has given final approval.

Over summer, trains will run every 20 minutes between 10am and 3pm on weekdays from Westall and West Footscray stations.

At weekends, they will run every 20 minutes from 10am to 7pm, and extend to East Pakenham every 40 minutes and Sunbury every 60 minutes.

These services will run alongside existing Sunbury and Pakenham/Cranbourne timetabled services, which will continue to operate through the City Loop.

The full timetable has not been released, but the government anticipates trains would run at least every 10 minutes from 6am to 10pm between Watergardens and Dandenong, with services every three to four minutes in peak hours.

Another letter sent to Metro Trains on September 25 by Rail, Tram and Bus Union national president Victor Moore, seen by The Age, formally requested information on the number of staff vacancies across the network and Metro’s plan to fill them.

“We also remind Metro that the arbitrary decision to leave positions vacant or delay filling roles can undermine job security and quality of jobs for our members, service quality, overburden current staff, and impact the safety and reliability of the network. It is therefore in the interests of both employees and the travelling public that these vacancies are addressed promptly,” Moore said at the time.

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