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

https://wiki-room.win/index.php/015_Sativex_vs_Epidyolex_What_Is_the_Difference

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