On June 18, Microsoft released the first public test build for "Windows Server vNext," its feature update for Windows Server. We're pretty sure this is part of the Windows Server 20H1 series, given that today's server test build number is 18917 and the Windows 10 client team released last week Build 18917 from the 20H1 branch.
Microsoft's blog post about the new build just calls it "Windows Server vNext." If it actually were the next semi-annual channel build, it would be part of the 19H2 branch. Microsoft still has yet to release any test builds of its 19H2 releases, even though the client team had been targeting "spring" for the commencement of 19H2 testing.
Sources have said that 19H2 may end being a very incremental update to Windows 10 and perhaps may have any brand-new features turned off by default. Microsoft officials have said nothing about how or when it will test or deliver 19H2, but have said there is a plan for a 19H2 release this year.
A quick reminder: Semi-Annual Channel releases of Server are focused on container and applications. They don't support long-term release features like Storage Spaces Direct, software-defined networking and shielded virtual machines. Users who need those capabilities should go with a Long-Term Servicing Channel release like Windows Server 2019.
Today's Windows Server Insider build includes some new functionality around the Virtual machines tool. There are Import/Export buttons now for importing and exporting virtual machines to a local volume or remote file share. In today's build, testers also get the ability to tag VMs on a Hyper-V Server. And according to Microsoft's post, "significant performance improvements" have been made to reduce page-load time in the Virtual machines tool.
Build 18917 adds new features to Azure integration functionality around the Azure Hybrid services tool, among other elements.
Microsoft also is working on a new version of the Windows Admin Center, which is the graphical tool for managing servers. Windows Admin Center is now up to preview 1906, which includes new features such as the ability to select individual Windows updates to install. There's also work toward providing users with a way to specify when they are offline in the Windows Admin Center in this build.
For a full list of features and known issues, check out the blog post about Windows Server 18917.
If Microsoft sticks to its current pattern, Windows Server 19H2, a k a Server 1909, should begin rolling out to users around October 2019 or so. Server 20H1 (Server 2003?) should begin rolling out around April/May 2020. Microsoft made Windows Server 1903 generally available last month.