After iOS 12.1.2 the official version released two days later, Apple began this morning to push iOS beta version 12.1.3 update to developers. In fact, iOS 12.1.3 beta content contained in this should be brought by the iOS 12.1.2 beta, and is marked is the second edition rather than the first edition.
When the 12.1.2 release iOS version number is 16C101, while iOS 16D after the beginning of the 12.1.2 beta version of a more reliable, today’s iOS 12.1.3 is 16D5032a.
In addition, Apple today also released at the same time macOS 10.14.3 beta 2, tvOS 12.1.2 beta 2 and watchOS 5.1.3 beta 2. The corresponding public beta has also been released.