Inputs For Sick Leave Generation

Dear Experts ,

For one of our client we need to generate sick leaves and casual leaves ,the conditions are as follows

sick leave- 5 days -     Prorata Basis -Need to Update the Quota on Hiring Date

Casual Leave -4 Days-Prorata Basis-  Need To Update on Hiing Date

one more condition is if the employee joined after 15th in any month no quota for that month ,quota for the remaining months need to update .

Here i am able to write a PCR for Midmonth Joined Employees but i am unable to update quota on hiring Date ,for this i wrote a pcr to check the Hiring date ,but my problem is if employee joined on 17th January so for the particular month no quota ,but as the pcr that will check hiring date it is leaving in this month and it is not giving quota from next month ,please experts give me some inputs how to  Achieve this .

Thanks In Advance

Anusha.k