It depends how you read which bits. I think they make regulations deliberately ambiguous.
I suspect that it was not deliberate.
As eric would say, only a Court could rule on the interpretation of legislation - and, if there is any ambiguity or uncertainty would do so on the basis of their view of (I suppose their "best guess at"!) the legislators' 'intention' . However, I know what my 'best guess' about that intent would be, and I suspect that a Court might well think likewise. As I've said before, that (my) view is that their intent was to ask for compliance with all the individual regulations in BS7671 (i.e as would be the case for a new installation).
A regulation (even a law) states that a rented property's electrical installation must comply (or conform) to the latest BS7671. In BS 7671 it states that electrical installations may be installed to other standards. Does that mean the property's electrical installation does not have to comply (or conform) to the latest BS7671?
As above, I very much doubt that such was the intent. Indeed, I think it very likely that the legislators didn't even realise that there might be possible 'loopholes' in the Introduction (but not actual 'regulations') of BS7671 - since, had they realised that, they would probably have been more explicit
In fact, I don't think that even BS7671 says anything about "other standards", other than the comment in the Introduction that things which were non-conformant with the current edition but which were compliant with earlier editions of BS767 are "not necessarily unsafe for continued use". Are you perhaps thinking of the OSG (the current version of which has, if I recall correctly, dropped the 'other standards'statement)?
The bottom line of my thoughts is that I think some people are probably trying to be 'too clever' in attempting to find technical loopholes based on the actual wording of the legislation. If I say that I want something to comply with a document which is a book full of numbered regulations, I would hope that most people would understand what I was asking for.
The 'let out',which ought to make this less of an issue, is that one would hope that sensible/competent inspectors would not give C2s to non-conformities with regs in BS7671:2018 when there were conformant/compliant with earlier (at least 'fairly recent') editions of BS7671 - and if they only give them C3s (if anything) that's not a problem (for landlords).
Kind Regards, John
