The Leave accrued in Advance value (on the Leave Details > Annual Leave & Holiday Pay tab) estimates the amount of leave an employee has accrued in advance since their last holiday anniversary. It is only a guide and is not a balance that is paid out. It is used to check whether an employee has enough leave accrued to take annual leave in advance.
This value is calculated by looking at the employee's Annual Leave Entitlement, the Current pay ended on date, then estimating how far through the year the date is in relation to the employee's next holiday anniversary.
The Leave accrued in Advance calculation is date driven and will change whenever the Current pay ended on date is changed.
If an employee works 40 hours per week, their Annual Leave Entitlement would be 160 hours per year (4 weeks x 40 hours).
The estimated Leave accrued in Advance would accrue at the rate of 3.076923 per week (160 hours divided by 52 weeks).
If the Current pay ended on date was 13 weeks since the employee's anniversary date the Leave accrued in Advance would show as 40 hours.