When you initially set up an employee, FlexiTime shortcuts the leave conversion process by just asking for annual leave available. This is essentially making any accrued leave current, and it means the employee starts with a single annual leave due balance, with no holiday pay, taken or accrued balances, as if they had just had a leave anniversary. From that point onwards the holiday pay and annual leave starts to accrue normally. The reason we do this is that for many new customers coming from manual payroll processes this is all they know.
This approach might work for you. By annual leave available we mean annual leave due as at the last anniversary plus any accrued since then. If this matches what your old system referred to as current annual leave due, then this is probably the best approach. So if you are doing this, you need to put zero in as the annual leave accrued since this has already been made due.
The following support centre article gives additional details about the various annual leave fields and how they interact.