Bus services should depart from timing points up to 1 minute early and 5 minutes late, and 95% of registered services need to operate within this window.
There are unplanned situations that can delay a bus service such as extreme weather conditions, accidents, and no-notice roadworks. But overall, bus services should be able to operate and run to their registered timetable.
To help establish any timetable issues, it’s recommended that operators monitor their routes which could include the use of daily logs. Also get feedback from drivers and keep records of anything that affects the reliability of the service.
Having full and regular contact with local authorities and other relevant parties (such as utility companies) may help to get advance notice of potential disruption to services, such as roadworks. Bus operators should communicate any potential disruption to passengers as early as they can.
Where appropriate, by regularly reviewing the registered timetables, operators can be proactive in submitting variations to timetables so they comply with the details they have registered..
Further information:
https://movingon.blog.gov.uk/2022/10/26/encouraging-bus-operators-to-keep-to-their-timetables/