If you make a ‘last minute’ decision to upgrade to W10, you might not succeed, due to servers getting swamped. So, if you’re really considering it, make your decision very soon. The free upgrade expires on July 29th.
Merely presenting as an option : A good option for those who want to load it and have just been waiting is the iso download from here ("Download tool now" button), should still work:
https://www.microsoft.com/en-us/software-download/windows10
That will also allow a person to do a fresh intall, my personal preference anyway. I'm not sure what exact version of Win10 that will download, it may be the same file that was out there in Nov or Dec. There may also be a place to download a newer version, I don't know. Of course an iso download would also need to be installed/activated during the free upgrade period to activate for free.
One would hope that once the free upgrade period is over all of those nagging promotional kb's coming down on the older Windows versions will stop.