In 2018, UK cannabis law was updated—not by changing the Misuse of Drugs Act...

https://www.tntmagazine.com/leisure-entertainment/leisure/why-is-cannabis-still-illegal-in-the-uk-the-history-behind-medical-cannabis-law/

In 2018, UK cannabis law was updated—not by changing the Misuse of Drugs Act 1971, but by amending the Misuse of Drugs Regulations 2001