If someone who works a five-day week books Monday to Friday off over a bank holiday, only 4 days will be deducted from their allowance.
If you would like to change this setting to make bank holiday bookings affect holiday allowance, you can do so at any time from the Bank Holidays tab of your Company Settings.
Simply click 'edit' next to the bank holiday you wish to update and then tick the 'deduct from holiday allowance' option. From here, click 'edit bank holiday'.
Any existing holiday bookings will be recalculated once this has been updated, although you may need to log out and back in before you see these updates.
NB: This is an admin-only task.