After assigning the Hunt Group feature to a customer site in Webex Calling, the next step is to assign a pilot number. The pilot number acts as the entry point for incoming calls to the Hunt Group, allowing the system to distribute these calls according to the Hunt Group settings, such as the specific sequence or pattern in which the calls are delivered to the designated users.
Cisco Reference
Webex Calling configuration guidelines provide details on setting up Hunt Groups, including the assignment of pilot numbers.