https://wccftech.com/beta-1-of-ios-12-1-watchos-5-1-tvos-12-1-now-available/

Apple has just released the first beta of iOS 12.1, watchOS 5.1 and tvOS 12.1 to registered developers.

We haven’t quite gotten over with the release of iOS 12, watchOS 5 and tvOS 12 and Apple has already started working on the upcoming iterations of its firmware. This includes the first beta of iOS 12.1, watchOS 5.1 as well as tvOS 12.1.