Great, thank you very much Kerry Charlton! I had a modified formula based on some google searches, but was not as advanced as what you provided.

Your suggestion is returning results, thank you.

I tried changing the "nb_of_hours" to be "Business hours (min)/60". Is nb_of_hours straight hours? I thought I read that it was, so thought I'd try business hours, but I am getting no results. Not sure if that would be related at all to the issue I'm waiting on ZD support to find out why the timestamp on our custom date field always has the time portions as 0.

Thanks again Kerry, very much appreciated!