It’s Still Not Clear How Microsoft Will Ship Updates to Windows 10 Mobile for Phones

At its January Windows 10 event, I asked Microsoft about how it would it update users on Windows Phone, since the firm has such a hard time doing so today. At the time, I was simply told that Microsoft had a plan in place, but that the details were forthcoming. So here’s what we know today.

Not much, as it turns out.

Despite recent excitement about a non-report in ZDNet, there hasn’t been any real news about how Microsoft will update Windows Phone users with Windows 10 Mobile in the future. But the software giant has in fact discussed this topic in more detail since January. It did so at WinHEC in March. The session, Upgrading to Windows 10, is a bit hard to follow as it is given by Ming-Che Julius Ho in (I believe) Chinese and translated in real-time by a revolving set of translators. But here’s the pertinent information provided:

There is no upgrade path from Windows Phone 8.0. If you’re Windows Phone 8(.0) handset was never upgraded to Windows Phone 8.1 or newer, you’re out of luck. You can’t get to Windows 10 Mobile.

The upgrade process will be very familiar to Windows Phone users. The upgrade process happens as it does now in Windows Phone, which is to say over the air, and using the familiar “grinding gears” UX will all know and love.

You can’t downgrade. Unlike with desktop versions of Windows 10, Windows 10 Mobile does not provide a way to “downgrade,” or go back to the previous Windows Phone OS version you were using. I suspect you will in fact be able to use the Lumia Software Recovery Tool to do that, however.

You can launch the upgrade from an SD card. If you’re using a low-end Windows Phone handset, or any handset in which the onboard storage is nearly full, you can simply download the Windows 10 Mobile upgrade to microSD and install it from there.

Project Milkyway. Microsoft goal is to deliver some kind of update to Windows 10 Mobile phones “every four to six weeks”—which can be patches, fixes, or new features. Project Milkyway is “a goal”—i.e. not a firm plan. It requires hardware and carrier partners to buy into this system so that updates can be tested and deployed regularly. Basically, Microsoft publishes OTA (over the air) updates to Windows Update, its hardware maker partners validate that the updates work correctly on their devices, and then carriers OK the update. (Or don’t.)

How updates really work. The following flowchart explains the update process for Windows 10 Mobile. An update is built, tested and signed. It’s placed in a preview server where Microsoft’s partners can validate it, and if there are no problems, it gets put on Windows Update. But this doesn’t mean everyone gets the update at the same time: Microsoft or its partners can determine when and where individual phones get individual updates, so they can control release by geography, device type or whatever other criteria. (That green box, “Validate OTA Updates on Retail Phones,” is where Microsoft’s partners, including carriers, step in. This is the logjam today.)

Long story short, Microsoft hasn’t really explained how—or if—it will really be able to bypass wireless carriers and deliver updates in a timely matter to Windows 10 Mobile users on phone. My educated guess—and to be clear, this is just a guess—is that it will use the Windows Insider Program to deliver “fast ring” updates early to insiders as part of Project Milkyway, and that normal users will only get them on the usual schedule, when carriers OK the updates.

But we’ll see. Experience has taught me not to get too excited when it comes to Windows Phone updates. And not to believe everything you read.