Less than a week after making available the first beta version of macOS Sierra 10.12.1, Apple today released the second for developers.
Compilation 16B2333a, which includes bug fixes and general improvements, does not yet have a definite date to be made available to the general public; in the meantime, tests are done with developers and Apple Beta Software Program participants, who are expected to get their hands on this second build soon.
Today, specifically, we only had this new beta for macOS even if none of the other operating systems.
Update · 09/27/2016 s 15:27
As expected, the new build is now also available to Apple Beta Software Program participants.