With the big news this past week that Microsoft is adjusting their Windows as a Service (WaaS) approach to give end users more control over when monthly and semi-annual updates are installed, you might have missed the opening of the infamous Windows Insider Magic Window.

Over on the Windows Insider blog, Senior Program Manager Brandon LeBlanc shared some details on the company’s planned approach to development builds in the various testing rings.

Here’s the TLDR:

• Fast Ring will soon begin to get Windows 10 (20H1) builds
• Current Skip Ahead ring members getting 20H1 builds will be merged back down to the Fast Ring
• Slow Ring will continue to host Windows 10 (19H1) Build 18362.30
• Release Preview Ring will soon receive Windows 10 (19H1) Build 18362.30 for expanded testing

The Magic Window is a period of time towards the end of a feature updates development cycle when testers can opt out of receiving Insider builds without having to do a clean install of their device.

So if you want to test 20H1 just keep your device in the Fast Ring. If however, you want to remain on the May 2019 Update, you will need to put your device into either the Slow Ring now or into Release Preview when Windows 10 (19H1) Build 18362.30 is released to testers in that ring next week.

Once the May 2019 Update begins its availability in late May, you can then opt out of further Insider builds by going to Windows Settings > Update & Security > Windows Insider Program and toggling off the Stop getting preview builds option.

If you have read through the above and are thinking something seems different then you are correct.

In the lineal sequence of feature updates, 19H2, the second feature update of 2019, is the next update expected to be released. Based on past Windows 10 feature update development cycles, 19H1 would be the next one up in Fast Ring however, that spot will be occupied by 20H1 instead. As you know, 20H1 is the designator for the first feature update for 2020.

Well, LeBlanc did mention 19H2 in his blog post about verifying Windows Insider settings:

We will begin releasing 19H2 bits to Insiders later this spring and will talk more about what that will look like in the near future.

This is also not the first time we have heard mention of the bits for Windows 10 (19H2). It was mentioned in the release notes for Windows 10 (20H1) Build 18860:

We will begin releasing 19H2 bits to Insiders later this spring after we get 19H1 nearly finished and ready;

The one thing left unsaid, and more details promised about it later, is where those bits are going to show up in the current Windows Insiders ring structure.

So to look at this let’s start with what we know:

• Windows 10 (20H1) will be developed and tested in the Fast Ring. Already stated and confirmed by Microsoft in LeBlanc’s blog post as noted above. This includes current Skip Ahead testers for 20H1 who will be brought back into the Fast Ring in the coming weeks.
• Windows 10 (19H1) Build 18362.30 is currently in the Slow Ring and will soon be in the Release Preview Ring. Also already stated by Microsoft in their announcement about changes to the WaaS process for Windows 10 beginning with the May 2019 Update.

Now here is where the real speculation begins:

• Windows 10 (19H2) bits may actually be distrubuted and tested in the Slow Ring exclusively. I suspect these could still be build to build upgrades however, they could appear as cumulative updates. No matter which update vehicle they choose, I believe 19H2 is going to be focused on fit and finish plus bug fixes and performance enhancements rather than big bang feature addtions.

Although Microsoft may never publicly label the H1 and H2 feature updates as major/minor updates, for at least right now, it seems that might be their focus with the 19H2 and 20H1 releases.

If the H1 release will be a major update, in this update scheme, the Slow Ring would return to availability after the 19H2 release this fall. That would allow Microsoft to use the Slow Ring to further test 20H1 development releases on a broader scale leading up to its availability next Spring.

Whatever happens, Microsoft seems to be listening to its users and slowing their roll when it comes to pushing out updates and their development approach to Windows 10 overall.

I have no doubt this is something to keep your eye on over the next few weeks and months.