The ninth edition of The Manual of Air Traffic Services (MATS) Part 1 (CAP 493) has been published and will become effective on 20th May 2021.
The Manual of Air Traffic Services contains procedures, instructions and information which are intended to form the basis of air traffic services within the United Kingdom. It is published for the guidance of civil air traffic controllers and may also be of general interest to others associated with civil aviation.
Source: CAA.