Hello jc denton
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It is cancelled due to construction work in the Hauenstein base tunnel until mid of August 2024.
Before the construction works started about two weeks ago, there were special announcements made for multiple days on each train between Basel/Olten and Basel/Zurich v.v. informing about cancellations and timetable adjustments during that period.
In order to keep up a reliable timetable and excellent train services, the train network has to undergo maintenance from time to time. Important work that affects thousands of people is preferably done during the holiday season where fewer commuters use the trains, just as now.
Kind regards,
Roland