It was a "free upgrade" to a paid service. Such a deal!
What part of
"The Windows Upgrade to Subscription tool, found in the latest Windows Insider builds, helps to manage certain volume licensing upgrades from Windows 10 Pro Anniversary Update to Windows 10 Enterprise. This binary file is not associated with the free consumer upgrade offering nor is it applicable to consumer Windows editions."
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I know, picking on Microsoft is still popular, even rightly so at times, and they might as well be lying or maybe tell the truth now and make a 360 later on, but still...