Do the periodic audits under CRA Module B+C cover the whole production system in the same way as module H?
No.
Under Annex VIII Part II point 8, the periodic audit duty is specifically to ensure that the vulnerability-handling processes in Part II of Annex I are implemented adequately. Module C separately leaves production conformity control to the manufacturer. So this is narrower than a module H full-quality-assurance assessment.
Limits Module B periodic audits to vulnerability-handling processes while Module C leaves production conformity control with the manufacturer.