I might add that since you've reserved your copy of Win 10 on Win 7, you might want to "take it back", although I've read that the upgrade won't take place without your permission. Question I'd ask is, "Did I give my permission to upgrade when I reserved my copy?" Yep, I reserved mine too.
1.You get to keep Windows 10 if you continue with the Insiders Program. Once you drop out of that program, Windows 10 is no longer valid, despite what was published in the multiply revised blog.
2. At this point, the only way to get Windows 10 free is to upgrade Windows 7 to Windows 10.