What’s New in Windows 10 Cumulative Update KB4598298 Jan 22, 2021 16:44 GMT New optional update now available Microsoft has released new optional cumulative updates for some Windows 10 versions, including 1909, with the company thus previewing some of the improvements it wants to include in the next full release for the operating system. The Windows 10 version 1909 cumulative update Microsoft published this week is KB4598298, and it increases the OS build number to 18363.1350. According to the official changelog, which you can find in full in the box after the jump, there are several improvements in this new update, including an EOS notification warning version 1909 is approaching the end of life.