Hi Andy, NIC, Elecsa and ECA are now owned by Certsure. If you hold 2391, this proves your ability to test and inspect. I don't think having a 17th edition qualification would hack it in court.For a long time the minimum requirements of NICEIC DI membership was the 2382 regs course, Elecsa were slightly higher. They are now owned by the same group and I don't think either require test and inspection quals to join. Not entirely sure now as I ditched my Elecsa membership a few years ago.
The membership of a scheme has nothing to do with your ability or competence to test and inspect work so not entirely sure what your point is here.