It’s always worth checking the beta update thread: Scrivener 3.0 Beta - Release Candidate 10 (Download Links & Change List)
In this case, the following from the release notes for B40 might help:
The last few betas have had Scrivener shaping up nicely, largely due to conquering the Windows mixed-vendor-world of crazy DPI variations and OS zooming. In beta 40, at last, we believe we have compilation of Styles on par with Mac, full implementations of Multimarkdown and Pandoc, and excellent plain text compilation of screenplays etc…
So that’s not an updated timeline, but it’s noting some key milestones…