We charge for domain renewals approximately one month prior to the expiry date to ensure that there's plenty of time to resolve any billing issues that may arise, missed notifications, expired credit cards, required authorization, etc. It's a lot cheaper and less frustrating than restoring an expired domain.
Please note that you will not lose any previously paid term. An additional full 12-month registration is always added onto any existing registration period remaining at the time we bill you.
Also, nothing to worry about if you don't see the domain's expiry date updated in your dashboard or in WHOIS records right away. Registries typically don't update that date until the old expiry date arrives, even though everything's already been done for the renewal.