This has been posted all over the place but if you haven’t seen it, this is a huge change.

To get it working, you need all your Apple TVs on iOS 18 DB1. Remove all your HomePods from your home if you have them. Then, you should see the option to turn off “Automatic Selection”. Turn it off and pick the Home Hub you want.

You can then readd your HomePods to your home. This process sounds painful but it’s actually pretty quick, HomePods remove, reset and readd to your Home fairly quickly. This whole process probably only took about 10 mins.