1903 was meant to be March 2019.
Yeah, those version numbers are weird.
1507 and 1511 shipped in July and November, respectively, but basically only because those numbers were given retroactively.
1607 shipped in August, 1703 in April, 1709 in October, 1803 in April, 1809 in November, and now 1903 in May. And those are still misleading — many didn't receive 1809 until well into January.
This seems like a self-inflicted wound, where product management wants semi-annual updates, engineers determine that they actually can't reliably ship in time, and marketing then comes up with wild confusing names like "Windows 10 May 2019 Update (Version 1903)". I'm sorry, what? Just name it 1905, then. (Heck, just leave the date out altogether. This is Windows 10.6, a.k.a. Snow Leopard.)
They are reporting issues now? My VMs went to 1903 last month but my physical W10 boxes aren't going yet as they are reporting not ready either.
I just hope Apple doesn't hire any of these Microsoft engineers.
I don't know how this is a bad thing. They're seeing telemetry that shows that some computers aren't booting after the update, and they've now narrowed it down to that particular driver in that particular version, so they're advising not to install in that case. Sounds like a positive to me.