As of July 24, 2020, Microsoft released the Windows 10 Insider Preview 19042.421 (20H2 development branch) for insiders on the Beta Channel (formerly the Slow Ring). The new release comes as cumulative update KB4568831. The announcement was made on the Windows Blog, where you can find references to this build and a list auf changes and bug fixes.
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KB4568831 insider preview re-released as build 19042.423 July 30
I'll post back again when this update goes public either this afternoon or tomorrow
KB4568831 update for Win10 v2004 build 19041.423 released 7/31:
https://www.catalog.update.microsoft.com/Search.aspx?q=kb4568831