I contacted iTunes support and they got back to me wanting my order number for some reason when they could have just searched for the problem. Oh well, I hope they fix it.
[Update: after 5 e-mail exchanges, being asked to re-download the show (which made no sense) and 2 consultations with a manager, iTunes tech support let the producers of the show know about the error, and now my Apple TV is showing the appropriate image for the most recent TV show.]
[Update: after 5 e-mail exchanges, being asked to re-download the show (which made no sense) and 2 consultations with a manager, iTunes tech support let the producers of the show know about the error, and now my Apple TV is showing the appropriate image for the most recent TV show.]