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

https://isabellasbestperspectives.quillnesty.com/posts/what-does-it-mean-that-cannabis-remains-controlled-in-the-uk

In 2018, UK cannabis law changed through an update to the Misuse of Drugs Regulations 2001—not the Misuse of Drugs Act 1971—allowing specialist doctors to prescribe cannabis-based medicines