I am trying to follow along. You have an engagement campaign set to send every two weeks with emails that are all only active for a week, correct?
It makes sense, but if you selected M-F an email will go out on Monday, Tuesday, Wednesday, Thursday and another one on Friday. It would then skip a week, and send again on Monday, Tuesday, Wednesday, Thursday and Friday of the following week. And so on.
As long as each email was scheduled to be active for specific weeks (8/11 to 8/15, then 8/18 to 8/22) without ANY overlap, this would work. You might get inundated with exhausted content notificatons. If there was overlap in the emails, you would risk sending two days in a row.
Does that make sense?