Hi All I wonder if anybody could help?

I’m trying to design a worksheet that automatically updates and populates dependent on certain conditions being met.

I have a list of students in Colum B

These students will be assigned a Stage in Colum C.

They will be allocated on a date (to a Teacher) in Colum D.

I’m trying to calculate a field in Colum E (Expected Completion Date) and I would like that to be 20 working days from the allocation date in Colum D unless the stage is equal to "PSR" when it should be 15 working days.

I'm also referencing holidays in cells B22 to B29 would should be discounted from the sum

I’ve tried using the workday function in a nested IF formula (in cell E2) but can’t get it to work, could somebody help at all as I can’t really move on until the first formula works!

I've attached the workbook with some sample data

Thanks in advance for any advice/why-is-vba-running-slowly