UK cannabis laws were adjusted in 2018 through the Misuse of Drugs Regulations...

https://delta-wiki.win/index.php/Why_Are_People_Saying_UK_Medical_Cannabis_Is_Legal_But_Not_Really%3F

UK cannabis laws were adjusted in 2018 through the Misuse of Drugs Regulations 2001, not the Misuse of Drugs Act 1971. This change made some cannabis-based medicines, like Sativex and Epidyolex, available on prescription but only from specialist doctors