The Government Says

Local government reorganisation: decision letter to Essex, Southend-on-Sea and Thurrock council leaders

Local government reorganisation: decision letter to Essex, Southend-on-Sea and Thurrock council leaders
Local copy of SoS_-_Letter_to_Essex_Leaders_25.03.26.pdf

https://www.gov.uk/government/publications/local-government-reorganisation-decision-letter-to-essex-southend-on-sea-and-thurrock-council-leaders

seen at 15:26, 25 March in News and communications.