Only 72 hours after the the sixth beta release of macOS 10.12.4 and iOS 10.3, Apple has made available the seventh iteration of the test software to developers, with little increment in release numbers suggesting an imminent release for users. [Updated with public beta info]
MacOS 10.12.4 contains Night Shift. The feature, first found in iOS 9.3 alters monitor parameters to reduce exposure to blue light to minimize user exposure to that part of the spectrum which potentially interferes with sleep cycles.
Dictation support for more languages has also been added, with improved PDFKit APIs eliminating some Sierra bugs. Beta 6 of macOS 10.12.4 had build number 16E189a, with build 7 sporting 16E191a — a very small increment as compared to previous weekly betas.
iOS 10.3 beta 7
Verizon customers also have iCloud-connected device calling added. Users running iOS 10.3 report that the 32-bit warning dialog box has changed, alerting users that an upcoming version of iOS will drop support for 32-bit apps entirely. Apple has not made clear what version that is, but iOS 11 is the likeliest candidate for the excision of the compatibility.
The sixth iOS 10.2 beta had build number 14E5273a, with Thursday's release having 14E5277a — also a smaller than normal increment. The relative "tightness" of the build numbers on both the macOS 10.12.4 and iOS 10.3 betas suggest a full release is imminent.
The first beta appeared in late January. Few releases take more than than the previously released six betas, much less a seventh release. In 2013, OS X 10.8.3 reached 10 developer betas before a full release.
Both releases are available to developers with registered devices. The iOS beta is available through the Software Update feature in Settings, and macOS users can update through the Mac App Store.
Update: Public betas are now available for members of Apple's Beta Software Program.