I'd expect that if you're not getting the offer (or should I call it pop-up advertising), then I wouldn't expect it to download in the background.
But there might be some more things that have to be installed for the silent download of W10
And the offer and enabling software most likely came with a recommended update. I don't browse from either Windows install, but figger I might as well stay current with the important stuff. Windows Update is usually the only time they're allowed to be online, a few app updates also.