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

https://www.slideserve.com/eogernrhbu/is-there-a-review-of-the-2018-medical-cannabis-change-happening-now

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