You can now set broadcast flows to run asynchronously. By running the flow asynchronously, you can send notifications to larger audiences or to add Wait elements to the flow. That means you can resume the flow after a certain event triggers, like if a customer opens an email.
Where: This change applies to Data 360 in Enterprise, Performance, Unlimited, and Developer editions. Broadcast flows are also available for Marketing Cloud Growth and Marketing Cloud Advanced editions with Data 360.
How: To run a broadcast flow asynchronously, in the Start element, select Async as the run type. With asynchronous broadcast flows you can add Wait elements to the flow. If an asynchronous broadcast flow is referenced in another flow through a subflow element, the asynchronous broadcast flow starts in a separate transaction while the parent flow continues.