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Passenger services are now operated by Chiltern Railways. The line is regularly used by freight services operated by DB Cargo UK and Freightliner. The trains, referred to as "binliners", carry waste from London to a waste facility near the site of the former Great Central Railway station at Calvert. For this purpose, during Chiltern Railways' Evergreen 2 project the line was resignalled with two new signals at Little Kimble, one for each direction of travel. These allow two trains to travel in the same direction, thus allowing a passenger service to follow the freight train or vice versa.
Services
The current timetable, produced for December 2019, offers one passenger service per hour in each direction, with services outside the weekday morning and evening peaks operating directly between Aylesbury and London Marylebone. In peak periods a shuttle service operates between Aylesbury and Princes Risborough, with a change onto connecting services needed at Princes Risborough for onward travel towards London. Not all services stop at Little Kimble.