Presumably, that means that Microsoft will start offering production VHDX images at that point (pro tip: the one currently being offered to Insiders is going to be the production image). When the new OS ships on October 5, ARM PCs will have Hyper-V support. That Windows 10 development branch eventually became Windows 11.

You'll notice that even with the Windows 10 version 21H2 update that's coming soon, the build number (19044) is still lower than the very first build to get Hyper-V on ARM.

This was due to a variety of reasons that led to Windows 10 getting enablement package updates instead of actual feature updates. Obviously, that happened in early 2020, and here we are Hyper-V for Windows on ARM hasn't shipped to non-Insiders yet. That's why the company started releasing virtual hard disks of Windows on ARM builds. In order to run a virtual machine on a Windows on ARM PC, you need an ARM image, just like on an M1 Mac. It's because beginning with Windows 10 Insider Preview build 19559, the Redmond firm started offering Hyper-V on ARM devices. However, that wasn't the original intent when Microsoft started publishing them.

This is the file that you'd use to get Windows 11 up and running in Parallels on your M1 Mac. What you can get is a VHDX file for a Windows Insider Preview build that's meant to be used in a virtual machine. Microsoft currently doesn't offer ISO images for Windows on ARM.

Windows 11 m1 mac