***!!!!!!FIXED!!!!!!***
Ok, after many hours of frustration with this darn popup notification, I have finally found a very very simple way to stop it.
Settings>Personal>Phone>CDMA Services>Network Service>Change to Home Only (done!)
So far, I have noticed no negative impact on my reception or signal and have not had the popup once. It was doing it several times per minute, just sitting here on my desk, right before I changed that. So, that is what is causing it and is a simple fix and easily reversed.
So, I may leave mine that way 100% of the time if it doesn't hurt my reception where I go.
However if it seems to impact my ability to receive a signal in certain places, then I will simply set it back to STANDARD.
I hope this helps others who are having this annoying issue!