Perhaps it's a question rather than a suggestion, but is there a way to list unaired episodes as Unaired?
The most common show with unaired episodes is Firefly. I'm assuming that the dates for the last three episodes come from... Syfy? Or the Canadian SPACE Channel? Or something. But the show never aired on Fox on the dates given.
But what if the unaired episode doesn't air anywhere else. What do you do then? The system won't let you enter 0s as a default.