A national train shortage could lead to fewer services than expected on the new Levenmouth rail link when it opens next spring.
Scotrail is unable to guarantee two trains an hour on the Leven to Thornton route, as originally planned.
And while a final decision has yet to be made, a rail insider told The Courier one journey an hour is more likely.
The long-awaited railway will connect with the Fife circle line, taking passengers from Leven to Edinburgh in around an hour and a quarter.
Rail campaigners say they are delighted with progress on the £116 million project, with the 5.5 miles of track completed last week.
But they are disappointed they may not get the promised level of service, at least to begin with.
Eugene Clarke, a member of the Levenmouth Rail Campaign group, said: “Scotrail cannot guarantee the rail service will start as described, i.e with two services per hour.
“They do not know if they’ll have enough rolling stock or staff.”
Train driver training to begin
Mr Clarke, who is also a Levenmouth Liberal Democrat councillor, questioned senior Scotrail staff at a campaign meeting this week.
He said: “I asked, was the service going to be twice an hour as had been promised.
“It was like pulling teeth to get an answer.
“But they did say it may not be possible to start with that level of service.
“They plan to start training drivers and conductors on the new line in January.
“But if they’re aiming to start running in April, that doesn’t give a lot of time.
“Their response was that was another reason why they may not be able to start with a full service.”
Mr Clarke is concerned additional trains may never arrive if they are needed elsewhere.
Public consultation on Levenmouth rail timetable plan
He added: “I obviously welcome the railway coming. I spent 10 years of my life campaigning for it.
“But there are valid concerns that I hope can be resolved.”
Scotrail says the public will be consulted on timetable proposals ahead of the railway opening.
A spokesman said: “A proposed timetable is being reviewed at the moment.
“It will go to public consultation later in the year and we will let customers and stakeholders know when that will start as soon as possible.”
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