Rail passengers should expect re-timed services as a result of railway engineering improvements this summer.
And the changes will come into place from Saturday, June 13.
The rail line through Winchburgh Tunnel, near Linlithgow, will be closed from June 13 until Monday, July 27 as part of work in preparation for electrification of the route.
As a result of the tunnel closure and the temporary timetable in place during this work, some trains on the Glenrothes line will depart at different times and may take longer to allow Alloa/Dunblane/Stirling services to use the same route.
Queuing systems will be in place at Edinburgh Waverley and Haymarket stations.
A ScotRail spokesman said: “We are advising commuters to set off earlier than normal, as some journeys may take longer.
“Customers should check our website for times before travelling.”
The tunnel closure is part of the Scottish Government-funded, £742m Edinburgh Glasgow Improvement Programme (EGIP).
For up to date travel information visit scotrail.co.uk