Support Ticket Escalations
From WHMCS Documentation
Found under the Settings menu, ticket escalation rules allow you to specify actions to take automatically if a support ticket has been in a specified state for a set period of time.
You can select the Departments, Statuses and Priorities that the escalation rule applies to. For example, in the picture below, a response will be automatically made to the client and an email sent to the members of the specific support department after 4 hours with no response:
Escalations are checked by running a cron file with parameters:
php -q \path\to\home\public_html\whmcspath\admin\cron.php escalations
Please note the space between cron.php and escalations. The command will run the escalations section of the cron file only.