[Alas Babylon!]

From Microsoft:

If I change my mind, can I cancel my reservation?

Yes, you can cancel your reservation at any time prior to installing Windows 10. Here’s how:

•Right click on the Get Windows 10 App or Windows icon located in right end of the taskbar.

•Select “Check your upgrade status”

•Select “Cancel reservation”

[SkyDancer]

Didn’t work - I did exactly that and there was no “Cancel reservation” to select. It just says “All Done For Now” “There is nothing else you need to do etc etc ....” and there’s the “CLOSE” button to click. That’s it.

[editor-surveyor]

Kind of like reserving your own funeral.
.