https://massgrave.dev/faq#why-is-the-windows-update-page-in-windows-10-enterprise-ltsc-2021-showing-your-device-is-no-longer-receiving-security-updates

Yes. It’s a permanent HWID license, associated to the hardware. No renewal needed, and it’s permanently associated to the hardware ID. If I reinstall the OS on the VM, it will reactivate without asking. And yet.

Yup. This is Win 10 IoT LTSC 21H2. Which should have updates all the way to January 13, 2032, if I’m not wrong. The HWID license is activated and attached to the VM. But…I’m getting a warning in Windows Update today.