Add validation to the End date of Unpaid Leave absence.

Summary:

We have a requirement of add validation to the End date of Unpaid Leave absence. The unpaid leave End Date is less than the System Date, it should be asking Yes or No to select in unpaid leave DFF.

Other than that it should not ask to select Yes or No options when we apply leave on same day or future date.

Our requirement is to allow employee leave with yes/no consent option . Storing the value yes/no, if he agrees to hr process of retrospective unpaid leave.

can we achieve this by using EL expressions added to End date?.