The Allowance Calculator is used whenever you make changes to Allowances or the Working Rota in your Leave Profiles. It will show you what the allowance was before the change, and what it will be after the change. You'll need to run the Allowance Calculator to update the allowances accordingly. If you make changes to a Leave Profile but don't visit the Allowance Calculator, employees' allowances will not change.
For more information on the Allowance Calculator, take a look at the following article: