A stream starts off with only on market listings. Over time, those listings get updated and some go off market, with the user being notified whenever this happens. Once a listing is in a stream, we never delete it unless a user clicks on that X to remove it, indicating they have no interest in that property. All notes and communications with the agent are recorded with the listing, and over time those listings will likely change into off market listings. There's a long tail of these listings that move down to the bottom of the stream as newer, on market listings appear at the top of the stream.