Microsoft has just now Rolled out Windows 10 1909 Build 18363.418 to Windows Insiders who are on Build 18362.10024 and in the Release Preview ring. In case, you are on Build 18362.10024 and still in the Slow ring, you will not receive this update.
You must have to switch to the Release Preview ring to pick up the final 19H2 (1909) build today. If you stick to the Slow ring, you will be updated to 20H1 branch very shortly. So rush to the Windows Insider Program settings and double check your options.
How to Confirm if you have Windows 10 1909 Build 18363.418
First of all, head to Settings > Update & Security > Windows Insider Program and confirm Release preview ring is selected.
Then Go to Settings > Update & Security and click on Check for updates from the right flank.
Follow the instructions provided by the system
See more on Windows 10 1909 –
Source – Windows Experience blog