This Order makes changes to electoral arrangements for Dorset following recommendations made by the Local Government Boundary Commission for England. Dorset is established as a unitary authority, with effect from 1st April 2019, by virtue of the Bournemouth, Dorset and Poole (Structural Changes) Order 2018 (S.I. 2018/648). The changes made by this Order apply in respect of local government elections held on and after the ordinary day of election of councillors in 2019.
Link: The Dorset (Electoral Changes) Order 2018
Source: Legislation .gov.uk