That would depend on who is inspecting and the electrician.
If you go through the LABC and don't use the electricians self cert system you can use the three part installation cert.
But if you are using electricians self cert system he has to be in control so you can only do what he allows you to do.
The problem is of course he can change his mind or even lose his self cert and it is not really a good idea to use that method.
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