It looks like AA will exit the ORD-BRU-ORD market. AA 88/89 are zeroed out. Last flight that is bookable departing Chicago is Sunday 6 November. It does not appear the flight will return next summer either.
That would be a shame.
For me that seems to only leave JFK-BRU-JFK on AA 172/171 which are the much less comfortable 757s, whereas the ORD service was 767.