From Adam Paish (UK): The British government’s flagship ‘Blue Belt Programme’ has been supporting a number of UK Overseas Territories with the protection and sustainable management of their marine environments since 2016. The territories currently involved in the initiative are: 

• Ascension Island
• Saint Helena
• Tristan da Cunha
• British Antarctic Territory
• British Indian Ocean Territory 
• Pitcairn Islands
• South Georgia & the South Sandwich Islands

On November 9, 2021, the postal administrations of Ascension Island and South Georgia & the South Sandwich Islands each released four stamps and a souvenir sheet (containing slightly different versions of the stamps) to publicise the programme. Stamps of similar designs will be released by Tristan da Cunha and the British Antarctic Territory as part of this issue, but no release date for these has yet been announced. The other territories are not expected to participate.