Historically Microsoft releases two big updates per year for Windows 10, the spring and fall updates (with included issues all the time). That schedule might be changing towards once a year.
Microsoft has reportedly shelved the previous Windows 10 update cycle. There should now be a "Major / Minor" publication plan. The background is apparently the delays and bugs associated with the last two versions.
The major update, the larger of the two, is still waiting with major changes, ie Kernel, Scheduler, APIs and drivers. The Minor update is tiny, but still much more extensive than the update that was usually done on Patch Tuesday. Obviously, features and the user interface are addressed.
Windows 10: one big update per year