The betas are moving into the next phase. Apple released the beta of iOS 12.1.3, macOS 10.14.3 and tvOS 12.1.2 for developers this evening.
Apple recently fixed problems with activating the eSim (embedded SIM) with iOS 12.1.2. A bug that affected the mobile connection in Turkey was also fixed. macOS 10.14.3 and tvOS 12.1.2 are both the second beta versions. They include the usual security, stability and performance optimizations.
The build numbers of the current versions are:
macOS Mojave 10.14.3 (18D32a)
iOS 12.1.3 (16D5032a)
tvOS 12.1.2 (16K5532a)