https://mailchimp.com/developer/transactional/guides/change-behavior-rules-engine/
Change Sending Behavior with the Rules Engine Guide | Mailchimp Developer
Set up searchable criteria that trigger specific actions with your Mailchimp Transactional account.
sending behaviorrules engine
https://docs.customer.io/journeys/queue-draft/
Sending behavior options | Customer.io Docs
options customer iosending