Well you've got me confused, Ed, (but that's not difficult; I'm easily confused!).
As recently as 16th April, Hansard shows that the only immediate change due to the Scrap Metal Dealers Act 1964 was that embraced within the Legal Aid, Sentencing and Punishment of Offenders Bill. That Bill has now passed into law
http://www.legislatio...0/section/146/enacted
but the only new offence is one of purchasing scrap metal for cash.
Other changes to the legislation (such as compulsory presentation of photographic ID) don't seem to have been enacted yet.
Further, the BMRA website has no press releases relating to photo ID:
http://onlinenewsroom.co.uk/bmra/
So I strongly suspect that there's no new legislation relating to to such ID. (There may, however, be new codes of conduct which fall outside statutory regulation).
For a definitive responses, email Ken Mackenzie at BMRA:
http://www.recyclemetals.org/contact_bmra
Chris