Could you attach your book (**.twbx)?
Please provide the packaged workbook for someone to look into it and provide the appropriate solution.
It will help if you attach a workbook, but it sounds like you are counting records in your data, you need to count unique dates.
COUNTD(if [Weekend Yn] = 'Y' or [Holiday Yn]='Y' then [date_field] else NULL END)
That's it! I've been trying to build it for a couple of days and I was almost losing my mind!
It was easy after all... yeah... after somebody did it for me!
Thanks Jennifer, much appreciated.