Thank you, Alfonso, for your reply and time. I came across information and a similar answer to my own question about how to switch between devices used for the Home Hub. But my experience says it is as simple as disabling (unplugging) the Home Hub device which status indicates “Connected”. This assumes there is an additional Home Hub capable device which status indicates “Standby”. After time (maybe even operation) the standby device will automatically become the connected Home Hub and even though unplugged the replaced device status goes to standby.
The information I found was at Apple Support page;
Set up your HomePod, Apple TV, or iPad as a home hub
https://support.apple.com/en-us/HT207057
In particular this section copied below;
Check the status of your home hub
You can check the status of your home hub, like if it's connected, in the Home app on your iPhone, iPad, iPod touch, or Mac.
- On your iPhone, iPad, and iPod touch: Tap House icon in the upper-left corner. If you have multiple homes set up, tap Home Settings, then tap a home. Look under Home Hubs to see if your home hub is connected.
- On your Mac: Go to Edit > Edit Home. Then look under Home Hubs to see if your home hub is connected. To check the status of a home hub in a different home that's set up in the Home app, tap Homes in the upper-left corner, then click a home.
To check if your Apple TV is set up as a home hub, go to Settings on your Apple TV, then click AirPlay > Room and make sure that you assign your Apple TV to a room in the Home app.*
If you have multiple home hubs set up, the primary home hub will show as connected. The other home hubs will show Standby as their status and will take over remote access if the main home hub is disconnected.
Thanks Again!