In March, Microsoft officials said they were tMicrosoft's new plan for rolling out non-security monthly updates (previously known as "C" and "D" week releases") will be slightly different from before.
Microsoft will be calling these optional releases "Preview" releases, going forward. They will be making them only available to a subset of users -- those on Windows 10 and Windows Server 1809 and later. And in the name of simplifying update management for IT, these Preview releases will be delivered in the "C" week, or the third week of each month, only. Cumulative security updates will continue to be delivered in the "B" week on Patch Tuesday.
Any IT pros using Windows Server Update Services (WSUS) to manage updates will no longer see Preview or "C" releases for Windows 10 or Windows Server in the WSUS channel, officials said today. And those in the Windows Insider and/or Windows Insider Program for Business will see the "in-development" versions of these optional cumulative updates made available in the Release Preview Channel during "B" week, Microsoft's blog post said.