Previously we're configuring all the subnets(including public and private) of the BYO VPC into install-config.yaml no matter it's for a public or private cluster install, but with the release blocker https://issues.redhat.com/browse/OCPBUGS-50839 found, we realized that we're not actually covering this in common private/disconnected+private cluster test, which means the subnets used in current private cluster testing is not accurate. For general private cluster usage, only private subnets should be used as there's no any public resources would be involved in private cluster. 

So the current configuration of private cluster need to be improved so that we can catch such issue more earlier.