Thanks Jamie,
Got pulled into something else yesterday but I'm back looking at your suggestions today.
I tried your suggestion of deleting groups 6 through 10 but I found if I deleted the DM.DriveID grouping, it did mess up the report layout so I had to leave that one in.
But that does seem to have resolved the issue as the drive dates are not appearing in descending date order.
i truly appreciate all of your help!