Timing issues with Vacation Accruals and Rollovers

For several years the payroll staff at my organization has had to manually adjust vacation balances whenever an employee has a rollover (which is based on their participation date (PADT).  We have been working with Oracle support for the past several months in an effort to make adjustments to our vacation DBA setup to eliminate the need to make manual adjustments.   We have been unsuccessful in coming up with a setup that will completely eliminate those manual adjustments and are curious what other organizations are doing to address the issues related to timing of accrual calculations, posting taken and processing rollovers.  We are on JDE World A9.2 base.  Our vacation DBA setup consists of paired DBAs – a DBA that accrues once each month based on months of service and one that stores the available balance for each year.  The amount of the accrual is rolled over into the new beginning balance when the employee reaches their anniversary date (PADT).