https://wccftech.com/big-news-for-slow-ring-windows-10-20h1-19013-arrives/

We saw reports earlier hinting that Microsoft has already internally finalized Windows 10 20H1 and is targeting to RTM in December. It appears it was all on point as the Windows maker has just released Windows 10 20H1 Insider Preview Build 19013.1122 to those in the Slow Ring.

With the release on Windows 10 November 2019 Update expected tomorrow, Slow ring will have nothing to do. But, Microsoft is already giving you some new work! Wondering what's included? Here is the complete changelog of Windows 10 20H1 Build 19013 (clean installation guide here):