On top of this morning’s iOS 12.1.1 release, Apple has also released tvOS 12.1.1 and macOS 10.14.2.
The tvOS 12.1.1 download is a minor update for Apple TV 4 and 4K owners, while the download for macOS 10.14.2 is similar in nature. Both releases bring bug fixes and performance updates.
You can install the tvOS update by going to System -> Software Update on your Apple TV. For the macOS update, go to the Software Update tab within System Preferences.