Virtual Machines blocked after system move

I have four physical systems. For the purpose of this issue, lets call them:

HN1.domain.tld HN2.domain.tld HN3.domain.tld HN4.domain.tld

When the systems were first set up, they were all using one set of IP Addresses, within the same subnet. HN1.domain.tld is the "Master" Cloudmin Controller. I had two VMs running (VM1 and VM2). VM1 was hosted on HN3.domain.tld and VM2 was hosted on HN4.domain.tld - and they were all working fine.

Physical systems HN3.domain.tld and HN4.domain.tld had to be moved, last minute, to another facility. They now use a different set of IP Addresses, on a second subnet. I added the second set of IP Addresses to the list of IPs which can be used. I am able to see and manage HN3.domain.tld & HN4.domain.tld from within Cloudmin and can access Webmin directly using their FQDN and the IPs each system is using.

However, the two Virtual Machines state "Parent host is down" in the Cloudmin control panel. When I ssh into either HN3.domain.tld or HN4.domain.tld and run the "xm list" command, both VM1 and VM2 show "b" in status (blocked).

I was unable to change the IP Address of the two Virtual Machines before the physical systems they were hosted on were moved, so I know this is where the problem started. Changing the IP Address of the Virtual Machines, within Cloudmin has no effect, as Cloudmin cannot access the Virtual Machines at this time.

What I need to know is:

How do I change the IP Address of the two Virtual Machines manually, now that they are on another subnet?

How do I configure Cloudmin so that these Virtual Machines are able to be managed again?

If it were up to me, the process would have gone a little differently, but now I'm in a bind and the Virtual Machines are live environments that I need to bring back online ASAP.

Any thoughts?