Hi Louise,
In addition to what Kevin has said about just working it out manually. You will find that there was a leave update in the software to allow for tracking historical leave balances.
This is why the system would not allow you to go back further than last financial year as that is possibly when you did your update.
There is no need to refresh as Kevin mentioned, just add it to the employee's file and make sure it accrues correctly from there.
Kind regards,
Sally McIntosh (sally@samsolutions.com.au)