I honestly don't care much that they're (probably) leaving. To be honest, I've never grown much attached to Iris and Cilan. Sure, they very dynamic characters and all, but I think it's time for them to go.
Iris is pretty much done. Cilan... it would be good if he got something, but I doubt they will touch his character much. He may get something in the episode with Purrloin and he will get another Detective Time, but I'm not expecting anything else.
So yeah, I'm more than ready for their eventual departure.