Is an option available to pay Absences at the employee's rate of pay when accruals were earned?

Summary:

We allow employees to carry over a balance of hours from year to year in their absence plan. If they use some of their absence balance for an absence, the hours pay out at their current salary rate. However many of the hours in their absence plan could have been earned more than a year ago, when they were earning a lower salary. Is an option available to pay Absences at the employee's rate of pay when the accrual was earned?

Content (please ensure you mask any confidential information):

Our absence plan is an accrual plan type that transfers absence payment information for payroll processing.