You need to certify that any new work complies fully with the current edition. That doesn't necessarily mean that you have to take an exam, but you need to be fully conversant with Amendment 2.
For an EICR, again you are reporting on the condition of the installation as to how it measures up to the current edition ie BS7671:2018+Amd2. So you need to be familiar with and have a demonstrable working knowledge of Amendment 2.
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