What order are broadcasts or blasts sent in?

Unless you are sending by custom score or time zone, text broadcasts and email blasts are sent to your audience in a random order.

For example, if you set up an automatic pause for the first 10k recipients, we will choose a random 10k from your audience.

While contacts are randomized each time, if you're sending that same audience daily with the same automatic pause, you may have overlap in the 10k sample each day. To avoid sending messages to the same phones or emails, consider adding a suppression that removes those that have recently received messages.