How to automatically adjust balance

Summary:

Content (required):

Hi Experts,

We have below requirement.

If an employee's person type is changed from 'A' to 'B' in the mid of the year and if the person has consumed all his accrual entitlement before the event change date, then the accrual in old assignment should be set to Zero. If the person hasn't consumed all of his accrual entitlement, then the remaining balance should be prorated.

Can anyone please help me understand a logic to achieve this requirement?

Thanks,

Pooja

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):