This new legislation (which was due to come into force on April 6th) has been postponed indefinitely.

Home Office have now announced that

“the commencement date for the legislation would no longer be 6th April 2016.” And

“a new date for commencement has yet to be confirmed.”

This seems like a bit of a mystery. Perhaps the volume of criticism led to a rethink? It has been argued that the law will be difficult to enforce.

Source: Psychoactive Substances Act Postponed Indefinitely