As far as I can remember 16th was two different BS numbers, BS 7671:1992 and BS 7671:2001 and the latter asked for RCD protection for all outside, and both asked for it for TT installations. I have got BS 7671:2001 some where.
At the time of BS 7671:2001 we had the old numbering system for the EICR which included code 4, this I seem to remember was would not comply with current edition if new it was a new design.
Since each edition has a clear date as to when designs had to comply, some thing designed in 1992 which complied then will still comply, however the inspector would need to know it was designed in 1992 so he would need to have all the installation and minor works certificates to show the design had not been altered, and would also need a copy of the BS7671 current at the time of the design, this was not really practical, and telling people it did not comply with latest edition was not really helpful.
So the coding changed, and it is now not linked to BS7671, so we need to look for potential danger, as I said I feel a push button as an isolator is potential dangerous, however I have a compliance certificate to say it complies with latest regulations. On commercial premises I have seen where people feel lack of the SPD is potential dangerous, I don't agree, but it is up to the inspector to decide.
It does not matter what we say, it is what the person signing the form said which matters, it seems one with the Land lord laws can take it to the LABC if you don't agree, good look with that, in the main they don't inspect themselves anyway. It is not under Part P so it has nothing to do with scheme providers, some do authorise members to do the EICR under the scheme, and it seems the scheme providers publish two forms one covered by scheme the other not, why anyone would buy forms which are a free down load from scheme providers when not covered by the scheme I don't know, maybe to try to con the client that it is covered by the scheme, the bit which says it's not is not in very large writing.
But the point is this is all a storm in a tea cup, fit a RCD FCU and one can rent without a problem, you have a minor works to show the work has been done, it is not required to have it re-tested, just attach a copy of the RCD FCU receipt and it covers, wrong I know, but that's how the daft law is worded. Since it supplies a room with a bath or shower it may need a compliance or completion certificate I will let other decide if that is required?