The Courts Service Act 1998 sets out the nature of the relationship between the Courts Service and the County Registrar. As the Deputy is aware, the post of County Registrar is a statutory officer, appointed by Government, with a number of different roles, including under-sheriff and returning officer functions.
When such posts become vacant, arrangements are made with the Courts Service and the Public Appointments Service to run an open recruitment competition to identify suitable persons for recommendation to Government for appointment. I understand the post in question will be advertised by the Public Appointments Service in the usual way.