Figure out occurence of overlapping date & time

Well, it seems like you've done it again. Your theory seems to bear it out. I ran that simple formula through all 30k calls and it looks like it gives me what I need.
What I couldn't wrap my head around was why I didn't need to check if a call overlapped with other calls beyond the initial start. Meaning... a call might only overlap with 2 calls when it first starts but because it lasts 2 hours it ends up overlapping with more calls.
But then I realized it didn't really matter. I just need to check when the initial call attempt is made. Because if I don't show that specific call as overlapping then the calls below it will capture the fact that was still ongoing, 2 hours later.
I'm still working the logic through my head but it's beginning to make sense. And it ends up being so simple. Just like we suspected it would be.
Thanks so very much.

Edit: I just went back and read through your post and you basically said the same thing I just did. lol. Well, I never said I wasn't dense. I had to go through the logic myself before I could truly understand it.