I installed Kde Neon on one ssd while it was the only drive on the board and then after that I installed Windows 10 on the other ssd while it was the only drive on the board (both are pci direct). I have the Neon drive, which is the drive in the number 1 pci slot, selected as 1st boot option in bios. I only use Windows when I need to update my Garmin or something like that and I have always just switched the boot order in bios to boot to Windows. I have never had a dual boot selection screen, but I booted up today and suddenly there is a dual boot selection screen. I even removed the drives and booted with only the Neon drive installed and still got the selection screen and Windows was an option. I guess it doesn't really matter, but one of the reasons I put them on separate drives is because I prefer not to deal with that.

Thanks so much for any knowledge anyone can bestow upon me

Any time grub is updated it runs os-prober - guess what that does ...
So it rebuilds the menu - it can be disabled, or the menu can be set to not display. I've never seen Neon, but any Ubuntu guide should work for changing the grub deffaults.

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As above. The os-prober generally runs when the kernel or some other package used on boot is updated -- the os-prober is run and adds the new kernel older kernels and any other OSs found to GRUB.
Edit: I know you may not be happy with this but it can, often, be a useful way of adding a Windows boot after a Linux one.

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Thank you syg00 and 273

So syg00, you say I can disable the menu or set it to not display and then you add a backup warning. Are there downfalls to setting it to not display or to disabling it? If it is set to not display, then really it is doing the same thing it is now where it waits the set amount of seconds for me to choose and then boots to the first option, I just will not see it. Is that correct? Is there any security risk in disabling it? I do keep all pertinent info backed up on USB, but is there a great risk of data loss by disabling the menu? I am guessing that it simply follows the boot order in BIOS if the menu is disabled. Is that correct?

So I added the line GRUB_DISABLE_OS_PROBER=true to etc/default/grub and now it does not show selection screen, but due to the 10 second blank screen before boot I believe it is only hidden and not disabled .....interesting.

I'm not sure that actually disables os-prober, because os-prober is not in the actual boot. If you want to disable the boot menu:in default/grub.

I tried that first and it does nothing.

This may be off topic, hopefully not as it seems related. I set /etc/default/grub back to the way it was before I changed it. Now in my BIOS boot options there are 2 options for the same drive, one is called Ubuntu and the other is called Neon. Both boot the drive successfully, but now the selection screen says Ubuntu instead of Neon when I boot to either of those options. They both boot neon, however.