UK cannabis law changed in 2018 with an update to the Misuse of Drugs...

https://echo-wiki.win/index.php/Is_There_a_Difference_Between_Lawful_to_Possess_and_Legal_to_Buy_in_the_UK%3F

UK cannabis law changed in 2018 with an update to the Misuse of Drugs Regulations 2001—not the 1971 Act—allowing specialist doctors to prescribe cannabis-based medicines like Sativex and Epidyolex under Schedule 2