In Settings -> Organisation Configuration, if you choose Stripe as your Gateway, Auto Charge/Auto Refund option becomes available.
Stripe does not keep deposits more than a week and releases them after 7 days automatically. Thus, for bookings more than a week, you need to renew the deposit after 7 days manually (that is avoiding the deposit and asking guests to do the process again).
However, if you tick Auto Charge/Auto Refund box, the system considers Stripe deposits as actual payments. That is when guests authorise the deposit, the amount is transferred to your account and after guests’ departure, if you do not want to Capture some or all part of it, it will be automatically refunded to them based on your setting in Organisation Configuration.
Please note that £3.00 per deposit transaction will be reduced from your account.