Temporary timetables will start on Monday (May 23) with revised timetables for Saturdays to be introduced in the future.
ScotRail says that a number of train drivers have not made themselves available for overtime or rest day working due to possible strike action.
Services impacted include those between Glasgow Queen Street and Edinburgh - via Shotts, via Falkirk High, and via Airdrie and Bathgate.
The other services are: Glasgow Queen Street - Falkirk Grahamston; Glasgow - Ardrossan/Largs/Stranraer/Ayr; Glasgow - Barrhead/Kilmarnock/Dumfries/Carlisle; Glasgow - Cathcart/Newton/Neilston; Glasgow - East Kilbride/Barrhead/Kilmarnock; Glasgow - Gourock/Wemyss Bay; Glasgow - Maryhill/Anniesland; and Glasgow - Paisley Canal.
ScotRail posted: “We’re aware how much recent disruption has been affecting our customers and believe introducing a temporary timetable will provide greater certainty and reliability for those travelling.
“We’ve been relying on drivers working overtime or on their rest days to run a normal timetable, as the pandemic meant that training new drivers was significantly delayed. Without Covid and that impact on training, we would have trained around an extra 130 drivers today.
“Following an announcement by the drivers’ union ASLEF that it will ballot for industrial action over pay, a significant number of drivers have been declining to make themselves available for overtime or rest day working. This has resulted in the recent disruption and our need to introduce a temporary timetable going forward.
“We want to resolve this dispute with the trade unions and move forward together to provide the safest, greenest, and most reliable railway we can for Scotland.
“In the meantime, we’re asking customers to check your journey as your train times may have changed.”
It has been revealed the last daily trains on key routes, including the Glasgow to Edinburgh will depart hours earlier than normal. The last trains on the Edinburgh-Glasgow main line will leave at 10:15pm in each direction compared to 11:45pm, which was the norm
Also the Glasgow-Aberdeen will be reduced to two-hourly.
You can find all the new timetables HERE.