Microsoft came out with major changes in new windows updates servicing model which was released on October 11 by Microsoft via TechNet https://blogs.technet.microsoft.com/windowsitpro/2016/08/15/further-simplifying-servicing-model-for-windows-7-and-windows-8-1/
Let’s review briefly what will be released each month and their official titles.
A security-only quality update
A single update containing all new security fixes for that month. This will be published only to Windows Server Update Services (WSUS), where it can be consumed by other tools like SCCM , and the Windows Update Catalog, where it can be downloaded for use with other tools or processes.This will be published to WSUS using the “Security Updates” classification, with the severity set to the highest level of any of the security fixes included in the update.
A security monthly quality rollup
A single update containing all new security fixes for that month, as well as fixes from all previous monthly rollups.This can also be called the “monthly rollup.” The initial monthly rollup released in October will only have new security updates from October, as well as the non-security updates from September.
This will be published to WSUS using the “Security Updates” classification.
A preview of the monthly quality rollup
An additional monthly rollup containing a preview of new non-security fixes that will be included in the next monthly rollup, as well as fixes from all previous monthly rollup. This can also be called the “preview rollup.”This preview rollup will be released on the third Tuesday of the month.This will be published to WSUS using the “Updates” classification as an optional update.
Note : Second Tuesday of Month (also referred to as the “B week”) & Third Tuesday of Month (also referred to as the “C week”).