Here is as I would do this (Except I'd use Defined Tables, and I'd add a table where all employees are listed, to allow the formulas to expand automatically whenever a new employee is added, or leaves for next year are added)

The sheet LeaveCal may contain dates for any reasonable number of future years, sou you don't have to edit it at every new year, and unless you want to see it for some reason, you can then hide this sheet, so users don't mess with it.

Attached Files

Overlapping dates request.xlsx (36.4 KB, 19 views)