System Restore in Dual Boot Situations

I have seen other discussions on this before but I have not been able to find a definitive answer that parallels my situation.
I dual boot Windows 7 and Windows 10 on 2 separate hard drives.
On each of the OS's I have configured System Restore to be "ON" for the C:. drive and "OFF" for the other drive on which the other OS resides.
I create a new Restore point on my Windows 7 and it works.
I then reboot into Windows 10 and create a Restore Point on its C: drive.
I then reboot and boot into Windows 7, only to find that the Restore point I created previously is gone.
If I then boot into Windows 10, the Restore point I created there is also gone.
Windows 7 is deleting the Windows 10 Restore Point and Windows 10 is deleting the Windows 7 Restore Point.
Now, Windows 7 can "see" the Windows 10 drive and vice-versa.
Is it possible - and I think this likely - that because I have set the "non-active" OS drive in each OS to Off in System Restore, it is becoming confused and deleting the Restore Points?
If that is the case, I can solve it easily in Device Manager by tell each OS to "Disable" the drive on which the other OS resides. This way the "other OS drive" will not even appear in the list of drives in System Restore.
Any thoughts?

I had exactly the same issue, however for past week system restore stays intact even after multiple boots to both systems.No idea why it works properly now, didn't before, haven't change anything. So I rely on back ups just in case. Also, I'm sure you know about it, but just in case for others: Win10 does not shut down your computer when you click shutdown computer. IT HIBERNATES it. Worse yet, it does not update drives directories on restart. So, you work in WIn 10, shutdown (but in reality hibernate) and change into Win 7. You work in Win 7, then go back to Win 10 and your computer has old directories in it's memory and corrupts all the drives that you changed under Win 7. If you dual boot Win 10, make sure you completely disable hibernation, otherwise you will have corrupted drives and no system restore will help you, even if it works.

I turned of Hibernate a long time ago but thanks.

Here are a couple of screen grabs to give a better idea of the situation.
Not a big problem, just curious.
I do multiple backups each day in both OS's.

Samsung is my Windows 10 drive.

Windows 10 is the first screen capture.

Strange.
I just cycled thru 2 complete reboot cycles on both OS's and all Restore Points are still there.
I know that certain Windows 10 updates will clear the Restore Points in that OS. Maybe it also clears all the ones it finds on all drives.
I'll keep an eye on it.
Thanks all.

Maybe MS finally fixed it in one of the updates? In the past mine would erase restore points in 90% of time, (but not always, mind you). For the past week or so all the restores are fine. I have similar setup to yours: Win 7 on SSD, Win 10 on hybrid drive and large data partition. It doesn't make sense to set restore points on data drive and setting restore for secondary partition could actually be dangerous: If I want to restore Win 7 C: drive due to some error for example, I don't want to restore Win 10 drive at the same time, not even sure how would that work, since Win 7 may not be aware of Win 10 registry, but could in theory replace some Win 10 files and royally mess everything up.

Well, the restore points are no longer being deleted, but wanted to restore my system and none of the 6 restore points I had, worked. All came up with error about registry files not saved properly or something. How difficult it is to save few files, incompetence of MS sometimes is so ridiculous and you can't even look at those files, because they're hidden, useless idiots.