Changes to Commission Decision of 9 November 2007 adopting a common specification of the national vehicle register provided for under Articles 14(4) and (5) of Directives 96/48/EC and 2001/16/EC (notified under document number C(2007) 5357) (2007/756/EC)
EU Decision 2007/756
Made by Railways (Interoperability) (Miscellaneous Amendments and Revocations) 2020
From legislation.gov.uk's record of changes, the official one: see it there.