Edit Annual Leave Entitlement

In the event of setting up a new employee, and their entitlement for A/L is accidently 0, please can you ensure that we are able to edit the annual leave entitlement for staff in their profile instead of having to create a new employee to find out pro-rata days or calculating externally? This would be operationally efficient. We can already add in the updated figure for full year entitlement, but the system doesnt calculate or do anything with the information.