Today, May 27, is the day. Microsoft finally is kicking off the process to roll Windows 10 2004, a k a the May 2020 Update, to mainstream users. The move comes a couple of weeks after Microsoft made the May 2020 Update available to developers.

Given the development process for Windows 10 May 2004 (the 20H1 feature update) ended back in December 2020, there isn’t a whole lot new to say about the 2004 update. Since December, Microsoft has made numerous tweaks, updates and fixes to 2004, but no new features have been added to it. In theory at least, this should mean smooth sailing for those updating to the new feature release, given it has had nearly six months of additional testing by Insiders before today’s release kick off.

Starting today, Microsoft is making 2004 available to “seekers, “ meaning those who proactive go to Windows Updates, check for updates and subsequently opt to download it immediately. As it has been doing with recent updates, Microsoft will be throttling delivery, providing the new feature update over the next few weeks to users with devices that Microsoft has deemed most likely to accommodate the 2004 feature update successfully. 

(From Microsoft’s blog post: “You may not see Download and install on your device as we are slowly throttling up this availability over the coming weeks, or your device might have a compatibility issue for which a safeguard hold is in place until we are confident that you will have a good update experience.”)

Officials said Windows 10 2004 is available via Windows Server Update Services (WSUS) and Windows Update for Business for phased roll-out. It also is available as of today via the Volume License Servicing Center (VLSC). I asked about availability on Visual Studio Subscriber downloads; and yes, it’s there starring today. And I’ve asked about Windows Server 2004 general availability and yes, it also is available starting today.

Windows 10 2004 includes a lot of fixes and updates, plus a handful of noteworthy new features. This is the update which adds Windows Subsystem for Linux (WSL) 2 support to the OS. (Don’t forget about Microsoft’s decision to remove the Linux kernel from the OS image back in March.) It also includes an option to download setup files from the cloud, instead of using local installation files. Windows 10 2004 adds an option to automatically restore open apps after a restart, as well. 

Here’s Microsoft’s blog post about what’s new  in the May 2020/2004 update that may especially be of interest to IT pros. Some of the new IT pro-specific features include improved controls and diagnostics for Windows setup and reserved storage; Application Guard support for the new Chromium-based Edge; FIDO2 security key support expansion; delivery-optimization; and new servicing/deployment enhancements.

Microsoft already has been testing via the Fast Ring new features which may or may not end up in Windows 10 20H2. My sources have said that Microsoft is planning to make the 20H2 build a small, incremental update to 2004 — the same way that 1909 was a cumulative-update-like experience to 1903. Microsoft officials have not said this publicly, however. The 20H2 update, codenamed “Manganese,” should be available this fall, if Microsoft sticks to its normal rollout cadence. Fast Ring testers should begin to see builds of 21H1 (codenamed “Iron”) starting later in June 2020.