Let's say you have people moving through an engagement stream of six emails. After they've passed through three of those emails, a new email is dropped in the stream. What will happen to the existing people in the stream?
-Will they receive the new email, or
-Will they continue to receive the remaining emails and receive the new email at the end?
It depends where you add the new content. If you add it to the top of the stream, everyone will receive it during the next cast. If you add it to the bottom, only those that haven't received all of the existing content will receive it (including all that have exhausted the current content). If you place it somewhere in the middle, then it will be received by anyone that has exhausted content above it (including those that have exhausted the current content).