This is one of those it is it isn't cases.
for clear guidance here's a quote from the guidance.
The results of the inspection and testing need to be clearly detailed in a report. Any observed damage, deterioration, defects, dangerous conditions and non-compliances with the requirements of the current edition of BS 7671 that may give rise to danger should be recorded and appropriately classified for remedial action.
It should be borne in mind that, as stated in the introduction to BS 7671, existing installations that have been constructed in accordance with earlier editions of the Standard may not comply with the current edition in every respect, but this does not necessarily mean that they are unsafe for continued use or require upgrading.
see clear as can be, depending on what you find.
if your doing the report and some half wit has flung a lead out of the window and plugged a jet washer into it them there's concern.
if on the other hand it's some old lady in a ground floor flat with no garden, car etc then no concern.
as for rcd leads what if the numpy doesn't use one.
come on shoot me down.
pps I wouldn't suggest a new CU