Foxdog you are quite correct in that the harmonised codes are not in statute yet.
To us, as suppliers, it is good practice to adopt the new codes ie. working to any more onerous points on the basis that it is anticpated that they will become statute in the near future. You will find that most surveyors have studied the harmonised codes and are working towards it implimentation.
Egg on our faces accepted if Parliment changes their mind !
Legally though it is not in statute and you can apply the relevant existing codes until it comes into statute.