Pro Plan users have access to configure a Domain Name Monitor. This monitor was introduced to allow users of our service to track the validity and expiration of the Domain Names they have configured in their accounts.
To configure a Domain Name Monitor, navigate to the Website that you want to configure the monitor on and then select Overview from the browse menu.
From this screen you have the ability to enable the Domain Name Monitor.
Also, be sure to check out the original Domain Name Monitor Blog post.