Windows 10 Mobile Build 14393.575 could be the next cumulative update for non-Insiders. However, the update is still testing and it will be released only if it passes the release criteria. Microsoft has compiled Mobile Build 14393.575 on 7th December and it could be the next cumulative update for Windows 10 Mobile.
It is worth mentioning that Windows 10 Mobile Build 14393.575 will only include various bug fixes and performance related improvements. We should not expect any major changes from the upcoming cumulative update.
The update could hit your devices next Tuesday (Patch Tuesday Update). Build 14393.575 will be available to non-Insiders only.