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

https://dlf-ne.org/is-cannabis-legal-in-the-uk-or-not-in-2026-clearing-up-the-confusion/

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