There have been some speculations of what the upcoming Windows 10 "Redstone 4" release will be called and as per a Twitter user Walking Cat (@h0x0d), it will be named the "Spring Creators Update". The Twitter user posted a command ‘Get-VMHostSupportedVersion’, asking his users to run it in PowerShell in the Windows 10 Insider Preview build numbered 17618 and see what happens. Soon after, someone posted a screenshot displaying the supported version names where the Windows 10 Creators Update (version 1703), Windows 10 Fall Creators Update (version 1709) are seen in the list, along with the upcoming Windows 10 Spring Creators Update version 1803.
The naming reference from within Windows is currently the best bet on what the upcoming installment of Windows could be called. The Spring Creators update is also expected to be the first major update to Windows 10, which will most likely come with AI-based features and machine learning.
Microsoft's previous major update, the Windows 10 "Fall Creators Update" was released in October last year. It was a major update for the operating system, which brought along overall designs and usability upgrades. New features were added to Microsoft’s digital assistant Cortana, Edge and Photos and the OS also received security updates and support for Mixed Reality (MR).
The company also recently announced that the Windows 10 S will be discontinued as a standalone operating system. It will instead be featured as a mode in Windows 10 and users currently on the restricted OS could be allowed to upgrade to the full-fledged version of Windows 10 Home, Pro for free and to the Enterprise version after paying a fee of $49. You can read more about it here.