An incident contact is the person or team that can be used to report a security issue. During a security incident is not the time to try to find the contact information for an organization that may be involved.
During a security incident is not the time to try to find the contact information for an organization that may be involved. Even if you find the contact information for the organization, it is unlikely that it is the main phone line that directs you to voicemail after hours.
They want a way to contact your organization 24 hours a day. This contact information should include a phone number as well as an email address. This number should be routed right to the SOC, NOC, or other staff that is going to be available 24x7.