Ben, trust what we say, Simple simon hit it on the head. The work that the builder has done can never be signed off, the builder was not competent to do so, and no one can do it on his behalf.
HOWEVER, do not fear, as the work replacing you CU and the subsequent testing that is involved is far more extensive than any minor works test that would be donefor the addition of a couple of sockets, and as a resuly the full Electrical installation certificate that the electrician will provide you with will include the testing of the circuit that these sockets are on and im sure if you raise your concerns with the spark doing the work he will pay attention to these sockets in question.
The spark is not signing off the work done, and yes its a issue that it was never notified, but.......in the real work its not so much of a problem, the work carried out this time is far more extensive and indepth so should provide a piece of mind in retrospect. and more to the point the EIC ticket that you will recive will more than satisfy any insurence or house sale
As i said dont stress buddy, go ahead have the work carried out and put it all behind you.
