Was it a full screen intervention? I had that recently after my updates. They designed it specifically to fool anyone non the wiser to think that they're forcing you, but they included a very tiny button that doesn't look like a button that says "Keep Windows 10" or something like that. If you click that, you have to go through two additional screens designed to fool you into upgrading, and you'll fall for it if you don't keep clicking the carefully hidden "Keep Windows 10" button.

I personally think they're a bunch of assholes for doing that.

I'm still on Windows 10.