Windows 10 Build 18312 was released on the Fast Ring last Tuesday and now the Build has rolled out to Windows 10 SDK Insider preview. The new Build does not offer anything new. The changes include Fluent Design improvement. A new effect of Acrylic Brush has been added and it has been named Luminosity. With this effect, the shadows do not appear behind any transparent panel without cutouts. However, there will be an API which will allow further customization.
You can download the Windows 10 Build 18312 here, but for that you need to be a member of Windows Insider. If you register for Fast Rings, then you will get Builds at greater frequency, but the Builds are less stable and come with a lot of bugs. You can check how to learn to select between Slow and Fast Ring in Windows Insider.
This build can be run in a production environment. So, you can use the build along with previous builds. The build can run in the production environment as long as the app targets a production version.