Microsoft's next probable major software release is 19H2, the April 2019 update. However, a build associated with a release in 2020 is the one that has most recently popped up for users in the Skip Ahead program. Despite this, the company insists 19H2 will be ready on time.
https://www.notebookcheck.net/Microsoft-starts-developing-Windows-20H1-ahead-of-19H2.410612.0.html