The Digital Economy Act has been passed Parliament and will lead to the mass blocking of internet porn to all UK residents. This includes the free tube sites and is not restricted to UK based websites.
The BBFC has now been given a new role as the UK internet porn censor. Final BBFC guidelines were published n October 2018.
Commencement of the BBFC censorship and age verification law will be on 15th July. Presumably there is a 3 month period after that to allow websites to implement the available age verification services