What is the correct way to remove a subordinate CA from an Enterprise PKI?

Question

Cryptography

good day everyone!
I ran into the need to withdraw two certification servers from the domain (highlighted in red in the figure):

I searched the Internet for information, everywhere either the final conclusion of the last center is indicated, or migration, which involves saving the name of the certification authority.
There are a couple of questions:
1. Will it be enough just to remove the AD Certificate Services role?
2. What will happen to clients who have received certificates from these centers: PKI02-,PKI03?
P.S. Certificates are issued for computers from the specified
P.P.S. centers. I did a certificate revocation for some clients, then published a revocation list, the client says that the revoked certificate is valid and therefore there is no need to request a new one