Windows 10 rollback

Hi
I have windows 7 licence for my PC.
I installed the free upgrade to windows 10 through windows 7.
I created a USB windows 10 install and used the setup on through windows 7.
I made a backup image of windows 10, reinstalled it and it is fine.
I understand there is an option to back within 30 days.

I can reinstall the windows 7 image easily.
I think both windows 10 and windows 7 now be valid for this computer?
I understand you cannot use both at once as a dual boot.

I really want to use windows 7 in the mean time.
When windows 10 is needed, in particular for directx 12 games, intend to use it.

The problem is I searched for a rollback option in windows 10. it is not there.
In windows 10, I went to settings, update & security, then recovery.
There are two options. Reset this PC and Advanced Startup. There is supposed to be a go back to windows 7 option, but it is not there.

So are both windows 7 & 10 licenced valid for the lifetime of my PC, not with both installed at once.
If not, what exactly are my options?

Thanks

Windows 7 and 10 licenses are both valid for your computer. You can restore the image of either one and run it, you can clean install either 7 or 10 and run it, you just can't have both installed at the same time without purchasing a second license for Windows.

The built-in rollback feature of Windows 10 is notoriously unreliable. It probably saved you some pain by just disappearing altogether

NavyLCDR said:

Windows 7 and 10 licenses are both valid for your computer. You can restore the image of either one and run it, you can clean install either 7 or 10 and run it, you just can't have both installed at the same time without purchasing a second license for Windows.

The built-in rollback feature of Windows 10 is notoriously unreliable. It probably saved you some pain by just disappearing altogether

Thanks for the info. That saved me a lot of grief.
Before I saved the windows 10 image, I ran disk cleanup & defrag.
It seems the disk cleanup operation removed the windows 7 that was saved.
It is good to know I can use either, by just restoring the appropriate image.