Well by September the team was pretty much out of it and they were awful the month leading up to it. The series August 5-7 vs Baltimore drew an average of 35k on a Tues, Wed, Thurs and that was the beginning of August. I don't think its a stretch to think they could draw 40k in September.
About the ratings, does SN not get revenue by selling ad slots for commercials of the games? So the more viewership goes up the more money they will get for those ad slots. I'm pretty sure SN doesn't sell the Ad slots far in advance either so depending on how the team does the more money they will get. The revenue would come into effect for the season after like you said though.