In 2018, UK cannabis law changed through updates to the Misuse of Drugs...

https://zionsniceinsight.readspirex.com/posts/why-is-cannabis-illegal-in-britain-the-history-before-1971

In 2018, UK cannabis law changed through updates to the Misuse of Drugs Regulations 2001, not the Misuse of Drugs Act 1971. This allowed specialist doctors to prescribe cannabis-based medicines like Sativex and Epidyolex under Schedule 2 rules