** Man of Leisure **
As I mentioned in a previous post, I was able to permanently resolve this issue by opening the “Home” app on my iPad and setting it up for use. Once completed, I followed the instructions on the ATV and the nagging message disappeared and has not returned. You might want to see if this approach works for you.Thanks this indeed put back the availability for TV OS betas, but brought back the issues with the Users Accounts and AirPlay HomeKit (please check the pictures attached).
I should add that I have at least one smart device that I added when configuring the Home app. I don’t know if that is a requirement for this approach to be successful.