I would appreciate some advice to ensure a project has begun before the application expires. The project is a barn conversion which has full planning permission and the expiration date of the permission is 25th November 2020. So far, the pre-commencement conditions have been discharged, and some surface water drainage and foul drainage have been installed. Drainage is in the definition of when a development has commenced so I have contacted the council for confirmation if the work is sufficient. They responded to say I need to submit an application for a Certificate of Lawful Use but from my understanding this is for projects without planning permission where sufficient time has elapsed or for projects which should not need planning, not projects which have planning approval. Any advice or experience on this issue would be greatly appreciated. Thank you.