Sch 4 para 12
If the impact of any proposed capacity restrictions is not limited to one network, the infrastructure managers concerned, including infrastructure managers that might be impacted by the rerouting of trains, must coordinate between themselves capacity restrictions that could involve a cancellation, re-routing of a train path or a replacement by other modes. The coordination must be completed— (a) no later than 18 months before the change of the working timetable if more than 50% of the estimated traffic volume on a railway line per day is cancelled, re-routed or replaced by other modes of transport for a duration of more than 30 consecutive days; (b) no later than 13 months and 15 days before the change of the working timetable period if more than 30% of the estimated traffic volume on a railway line per day is cancelled, re-routed or replaced by other modes of transport for a duration of more than seven consecutive days; (c) no later than 13 months and 15 days before the change of the working timetable period if more than 50% of the estimated traffic volume on a railway line per day is cancelled, re-routed or replaced by other modes of transport for a duration of seven consecutive days or less. The infrastructure managers must, if necessary, invite the applicants active on the lines concerned and the main operators of service facilities concerned to get involved in that coordination.