I had gotten used to the data session closing when a form is closed, and any tables that had been opened while the form was intantiated were closed.
Now I'm discovering that the data session is remaining open after closing the form, and any tables that were opened are still Used(). Only the tables specifically listed in the data environment are being closed.

I have AutoCloseTables=.t. which is why the tables in the data environment are being closed, but why aren't the others being closed and the data session being removed (it's listed in the 'Data Session Window' as Unknown(2) or Unknown(3) etc.)