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

https://wiki-book.win/index.php/Licensed_vs_Lawful_to_Prescribe:_What_Is_the_Difference_in_UK_Cannabis_Medicines%3F

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