Late last night Regional Rail Revival announced that works on the Ballarat line upgrade had gone overtime and would need an extra 24 hours to complete.

Trains are now expected to resume on Wednesday morning.

It's been a frustrating two weeks for passengers with one extension already after the expected 10 day stoppage. Trains were expected to be up and running by Monday morning

Rail Projects Victoria announced at 7.30pm Monday that coaches would replace trains for a further 24 hours to allow for the construction blitz to be completed.

"We have been working around the clock to get these critical works completed but unfortunately have run into unexpected signalling complexities related to the final commissioning of a new stabling facility at Maddingley," Regional Rail Revival director Mark Havryluk said.

"As a result, we've had to extend this construction blitz for another day," he said.

Twitter had been abuzz during the Monday evening commute with dozens of train travellers saying they had been told that services would not resume as scheduled on Tuesday morning, but as late as 6.30pm V/Line's Ballarat Line account was still maintaining the trains would run.

"We are sincerely sorry to Ballarat line passengers for the continued inconvenience, particularly at this late notice, however we must always put safety first," Mr Havryluk said.

"Signalling is absolutely fundamental to the safe and efficient operation of a train line and something we cannot compromise on."

The coaches will replace trains between Southern Cross Station, Ballarat and Wendouree until the last service on Tuesday.

Passengers should allow 45 minutes' extra travel time while coaches replace trains.

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