What happens when engagement member become un-paused?

Hey Abdallah,
That is correct.

Every Engagement Cast, each lead looks through the entire stream for the first peice of content they have not received. This behaves exactly the same if a lead becomes unpaused. 

So leads do not keep track of which spot they are in the stream. They start at the first peice of content and keep skipping emails until they find one they have not yet received.

Pausing them simply prevents leads from being cast to. Once they are unpaused, everything resumes as normal.

Best,
Will

Thanks for the terrific answer. It makes a lot of sense. 

Does that also mean that if you add new content upstream of some members then they would recieve this content during the next cast? In other words, the order of the content will not be followed if newer content is added upstream?

Thanks again.

That is correct, as well!

If you add a new piece of content to the first spot in the stream and no leads have received it yet, all the leads in your engagement program will receive that email on the next cast since it is new and at the top of the stream.