Answer
Lightning Payroll does not automatically create every historical leave grant for old years when an employee is first set up. It uses the information available from the employee's setup date, anniversary dates, completed pays, historic earnings, and manual adjustments.
If you are moving an employee from another payroll system, enter the opening Annual Holidays, Sick Leave, and Alternative Holiday balances as manual adjustments. Then check the balance breakdown and grant schedule before completing the next pay.
This avoids double-counting leave that was already accrued, paid, cashed up, or adjusted in the previous payroll system.