Uncertain if you moved from an insider or preview version. Users upgrading from 7/8.1 say it provided the option menu.
You're pushing the update aggressively. It looks like you noticed a Reddit post or similar. The screen I'm seeing is the same now. Upgrading is possible—just let me know if you need to report it.
You haven't made any changes yet. Are you seeing that menu option? I saw it in the mini news thread.
You're using the ISO download and upgrading from Microsoft's site instead of letting Windows Update handle it. A few others have done the same, including me. Mine is now installing. But after finishing, I'm considering erasing it and starting fresh for a cleaner SSD. I saw the screen, but it doesn't show up in the Windows Update section. That's why people who did this method don't see this window or screenshot.
I saw the update a month prior. It had issues, so I went back to version 7 and fixed it.