Xamarin SDK 1.22.4648 is now ready to download. You can access the documentation here. The online API documentation is availabe here. And you can see the package on NuGet here. We did release version 1.21-3280-alpha earlier this year, but as far as official release builds, the last release was version 1.5.88 back in Jaunary 2018, so this update is long overdue!
The MAJOR and MINOR version numbers of the Datalogic Xamairn SDK track the version numbers of the Android Studio SDK, i.e. Xamarin SDK v1.22.x contains all of the features available in Anroid SDK v1.22. Therefore, this update includes all the new features introduced in the Android Studio SDK from version 1.6 all the way up through version 1.22.