Windows 10 version 1909 is the next major release of the OS, which is expected to available in late September or October of 2019.
If you current have the Windows 10 May 2019 Update installed (version 1903), then your computer or device will receive this as a cumulative update (similar to the monthly “Patch Tuesday” security updates via Windows Update) only a much larger download.
New Features: A preliminary list of new features can be viewed here --->
New Approach For Releasing Upgrades / Updates: Microsoft plans to initially offer the update only to devices known to be compatible (determined by their Windows Insider testing program) to help eliminate problems. When the new version installation success rate has been positive, it will be made available to more users.
Protect yourself, create an Image Backup: Either way, major, minor or monthly “Patch Tuesday” update, create an Image Back of your “Entire” disk drive. Should something go wrong during or after the update is installed you can use the backup you created to recover/restore your computer back to the way it was prior to installing the update.
Iit appears that Microsoft has the abandoned the twice yearly major upgrade approach and will slim down to once a year with the next major update (20H1) available sometime the March to May 2020 time frame.