UK – COVID-19: Use of callsign suffix ‘ALPHA’
With immediate effect, search and rescue flights using the 'RESCUE' callsign may be flown as flight priority category 'A'. The callsigns of such flights will include the suffix 'ALPHA'. All other flights undertaken by HM Coastguard Helicopters will continue to use the RESCUE callsign. Manual of Air Traffic Services Part 1 (CAP 493) Section 1, ["]