To extend the expiration date for this site collection, click the link below:
http://url.aspx

Otherwise this site collection, including all of its subsites, might be deleted.

If this site collection is no longer needed, you can delete it by going to http://url.aspx, and selecting “Delete this site”.

Please note – When a SharePoint Web site collection is deleted, all Web sites, content and information which were part of the site collection are completely erased. The site can only be restored if a backup exists.

To update the settings for this alert you will need to venture into Central Administration.
Central Administration > Application Management > Site Use Confirmation and Deletion

Select the Web Application you want to update and then click OK.