A6 between Shap and Kendal, junction with Breasthigh Road, byway 355003 showing traffic prohibtion sign
Breasthigh Road, Cumbria is a 3km byway open to all traffic and is an attractive ride. It links Borrowdale with Bretherdale and is a link in the TET (Trans Euro Trail). There are several other shorter byways close by so it looks possible to make a tour. This is Borrowdale near Shap on the A6 trunk road, formerly in Westmorland and distinct from Borrowdale near Derwent Water in former Cumberland.
I wanted to check out the actual situation on the ground as Breasthigh Road is noted as closed to motor vehicles for restoration works on the website of the national park authority. The project plan shows works to have started in May 2022 but no update is shown since tree planting in Autumn 2022. Meanwhile the definitive map for Cumbria shows Breasthigh Road, byway 355003 and its connections as open.
Conclusion. Works appear to be complete. The temporary prohibition of traffic notice has been extended. It is not legal to proceed until 1 May 2023. And the definitive map is not definitive in this case.