Over two weeks ago, Microsoft released Windows 10 build 18875 to the Fast ring, merging Skip Ahead and Fast. Since there were a lot of people upgrading from 19H1 at that point, it was soon discovered that there was an issue with the current cumulative update that prevented users from upgrading to 20H1. Naturally, the build was pulled for anyone that was still on build 18362.53.
Today though, there's a new cumulative update, KB4497093, that fixes the issue. It brings the build number to 18362.86, and contains the following fixes:
This Cumulative Update includes the fix for Windows Insiders in the Fast ring who were unable to update to the latest 20H1 build from Build 18362.53.
We have made general improvements for users in Japan or use the OS in Japanese including fixes for the Japanese IME and fixes for date and time issues.
We fixed an issue where UWP VPN plugin apps might not be able to properly send packets through an established VPN tunnel on an IPv6 only network.
We fixed the issue causing updating to Build 18362 to fail to install with an 0x80242016 error.
Microsoft has released several patches for Windows 10 version 1903 since it was offered to the Release Preview ring. The company promises to service it while it spends a full month in the ring before releasing it to the general public late next month.