Trying to identify date overlaps among multiple centers

Our company has multiple centers and I am working on creating a spreadsheet that captures dates of all of the projects going on for each center. As we add projects I add the dates to the bottom of my list so I am looking for an easy way to identify when there is overlap of dates when I add a new project for the individual centers. I am attaching a spreadsheet with a tab that shows a snapshot of how I have it setup and then a tab to show desired. The difficulty is that the centers will not always be in order like the example shown and we will have thousands of rows. I tried several formulas with no luck and I'm not familiar enough with excel formulas to know how to best approach this. Any help would be greatly appreciated! Thanks Example.xlsx

Yes that would help overall but what I'm looking for is within each center grouping. So is there any overlap within the Bensen center dates, Mesa dates, etc. In your example, in green, lines 31 and 34 should have been "overlap" and only 31 is showing up. If different centers overlap with each other that's fine we are really more concered about overlap within each individual center. Thanks

Wonderful, it looks to be working!! Thanks so much!

Any suggestions on how I would highlight the word "Overlap" only when the finish date is today or future dates? I have tried a couple different ways with conditional formatting but I don't seem to be getting what I want. Thanks!

Thanks! How would I fix the overlap column to not show anything when there is no data entered in the row?

The example attached is a snapshot. Thanks
Example2.xlsx