It looked like Windows 10 build 17133 was going to be blessed as the 1803 update, but that plan has been derailed. Though the build was pushed out to Windows Insiders on the release preview ring—an action that, in the past, has indicated that a build is production ready—it turns out that it had a bug causing blue screens of death.

Microsoft could likely have addressed the situation with an incremental update, but for whatever reason, it didn't. Instead, we have a new build, 17134. This build is identical to 17133 except that it fixes the particular crashing issue. Fast ring Insiders have the build now, and it should trickle out to Slow ring and Release Preview ring shortly. If all goes well, the build will then make its way out to regular Windows users on the stable release channel.

When will that happen? That's less clear. The expectation was that 17133 would be pushed out on this month's Patch Tuesday; with the delay, May's Patch Tuesday would be the logical opportunity, though if Microsoft is happy that the build works, there's no particular need to wait.

The other unknown is what the release will be called. In addition to their build number, past Windows 10 major updates have all had a branded name—like the Anniversary Update and the Creators Update—and a version name, which is a four-digit number that's made up of the last two digits of the year and the two digits of the month that the build was made.

Build 17133 had the version name 1803, because it was made in March of this year. Build 17134, made in April of this year is... still 1803, and now the names have no meaning. That's a shame; Microsoft would probably do well to slide the builds to April (and October) because, as things currently stand, the company is on track to ship "Windows 10 version 2003" in March or April 2020, and you can just guarantee that some piece of software will somehow think that it's running on Windows Server 2003. Version 2004 would neatly avoid that risk.

The branded names have previously been announced many months ahead of release. That hasn't happened this time around. We'd love for the branded names to disappear—the semiannual Windows updates should be routine events, not marketing opportunities—but there are rumblings that this version will have a branded name. For a time, previews of the next Windows release (the one due in October) gave 1803 the name "Spring Creators Update." More recently, Microsoft staff have used the term Windows 10 April 2018 Update, which is much more perfunctory.