Because Windows 10 19H1, also referred to as version 1903 and May 2019 Update, and Windows 10 19H2, known as version 1909 and November 2019 Update, share exactly the same servicing content, they obtain the same cumulative updates as well.
The update that Microsoft released today to the Release Preview ring is KB4522355, which is thus available for both those who run 19H1 and 19H2 builds. This cumulative update comes alongside a brand new servicing stack update labeled as KB4525419.
A changelog for this new cumulative update isn’t yet available, but after installation zinc heightens the OS build number to 18362.446 on Windows 10 19H1 builds and also to 18363.446 on Windows 10 19H2.
Coming later this month for production devices
Probably, exactly the same cumulative update may also be released later this month to production devices running Windows 10 May 2019 Update (version 1903). The software giant published a brand new batch of cumulative updates for Windows 10 on October 15, but version 1903 wasn’t part of the rollout.
Simultaneously, this pack of improvements may also be included in the final build of Windows 10 November 2019 Update (version 1909) when it launches next month.
Windows 10 version 1909 itself lands like a cumulative update, so it includes all the previously-released fixes too. According to a recent leak, this Windows 10 feature update is projected to land on November 12 for that first wave of devices. November 12 also marks the following Patch Tuesday cycle when Microsoft will publish new cumulative updates for all Windows 10 versions.
We’re still awaiting a changelog for cumulative update KB4522355, but as it takes place every time, we’re unlikely to obtain one before the same update becomes available for production devices.