MacRumors published a story that Apple has released the first beta of tvOS 16.6 to registered developers.

Apple Seeds First Beta of tvOS 16.6 to Developers

Apple today seeded the first beta of an upcoming tvOS 16.6 update to developers for testing purposes, with the beta coming a day after the launch of tvOS 16.5.

Registered developers are able to download the tvOS 16.6 update by downloading a profile on the Apple TV using Xcode.

  Apple Seeds First Beta of tvOS 16.6 to Developers