Windows 10 1909, aka 19H2 build 18363.327. the September 2019 Windows 10 update is now released for few insiders. Users will start seeing this update just like a normal update when you check on Settings -> Update & Security -> Windows update. If this update was showing to you, and you want to know whether you can install it or not, then my suggestion would be no, because Microsoft has clarified that all the features of Windows 10 Version, 1909 was not migrated yet.
Here, is what Microsoft Says..
Insiders in the Release Preview ring who get 19H2 Build 18363.327 today will not see all the 19H2 features the Slow ring currently has as not all the features have been incorporated into the build yet. Because of the differences between the way the 19H2 updates are packaged between the Slow and Release Preview rings, Insiders in the Slow ring will not be able to switch to the Release Preview ring and get updates yet. Insiders who are thinking of switching rings should stay put for now. We will communicate to Insiders when it is ok to make the switch.
If you are a normal standard Windows user, then we have a happy news this time because Microsoft (after serving all of the bugs in previous builds) decided to send this update to users as just a normal cumulative update which means like a normal Tuesday update which i guess won't consume lot of data to download than previous builds, but as a usual suggestion. Control your wish to install the Windows 10 version 1909 as of now on Main PC, and wait for Microsoft to fix all the bugs.