The callout feature is a great way to send notifications to a large group of people. But not everyone who receives the callout needs to see the same information. By adding multiple Alerting destinations you can tailor messages designed for that specific group.
First, make sure that all destinations are set in the Alerting section.
Then you can add messages and drag each destination to the tailored message. Pressing one button here to trigger this example Callout will send separate messages specifically designed for the Administrators Team, Emergency Attention Required Notification Feed and to a specific User