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

https://lorenzosuniquenews.rivetgarden.com/posts/what-is-the-house-of-commons-library-briefing-on-medical-cannabis

In 2018, UK cannabis law changed through an update 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