V/LINE says coaches will replace trains on the Ballarat line on Thursday if a full-day stoppage goes ahead as planned.
The rail authority is preparing for a series of rolling stops over the coming two weeks as the Rail, Tram and Bus Union (RTBU) fights the regional train provider over conditions.
There are planned stops on the Bendigo, Echuca and Swan Hill lines on Wednesday while Thursday will be Ballarat's turn with no trains scheduled on the Ballarat, Ararat and Maryborough lines.
In a statement published on the V/Line website, the authority is asking passengers to allow an extra 60 minutes on their journey.
"We will do everything possible to minimise the impact of the industrial action, to help our passengers get where they need to go during the festive season," the statement said.
"We will ensure passengers are given as much notice as possible of service changes.
"Information will be communicated on our website, the V/Line app, social media and information displayed at stations. We would like to thank passengers for their understanding during this time."
The RTBU says the strike action is a last resort with staff currently working under and EBA which expired four months ago.
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