PKI questions with an unplanned renewal of the SubCA

I think I understand how this will work, but need some feedback for reassurance, since I'm not great with PKI.

Our current SubCA needs to be renewed a couple of months prior to its actual expiration. No big deal, we'd need to do this anyway.

What I'm concerned about is the effect on the SCCM primary, MPs and DPs.

I believe, as long as we keep the certificate chain and the same key pair, the transition should be smooth and existing clients/servers will update as the expiration time hits.

Questions:

1. Do I need to update the certificate in the Communication Security tab of the site server, specifically the Trusted Root setting?

2. Can we expedite the clients and servers getting the updated certificate date by using the "Reenroll All Certificate Holders" action on the CA?

This all came about because the Network team deployed a wireless certificate with client auth and a longer validity than our CM certificates. Clients stopped reporting in, especially after imaging because the client is choosing the new Wifi Cert and not the CM client certs.

We've been working with MS for a week on this issue and after all the troubleshooting, this is the best course of action to fix the situation so that the client certificates are newer.

For the future, we're going to create a new Cert Store on the client, put CM client certificates there and point to it with the CCMCERTSTORE= parameter going forward to avoid this in the future.