When having domain names set to 'auto-renew', in our billing software, this means that your wish to have a renewal invoice generated for this domain name, and that, if you credit on your account, that credit will be automatically used to renew the domain itself.
We never renew domain names and retrospectively charge you, we only ever renew domain names once you have paid for them or using credit on your account.
When a domain name is not set to 'auto-renew' we will not generate a renewal invoice for the domain name, you can still renew it any time from your client area however we will take no further action in respect of the domain itself, letting it lapse if no action is taken by yourself.