Julia,
Not sure whether you will be able to answer this so far ahead but on the America Heart and soul holiday we are in Chicago 3 nights (Mon, Tues & Wed).
Would you be able to tell me which night the included excurrsion to Kingston Mines Blues Club will be ?
For information to others doing this holiday I've been in the club more than once and its a bit different, the music starts at 9pm (until 3am) and there are two acts scheduled each night who alternate every hour (3 stints each).
However they dont play the same stage the audience changes rooms between acts, time it well 5 mins before end of act to get better seat in the other room.
I'll assume the JY group wouldn't be staying until 3am but you can easily flag taxis outside if anyone wanted to stay and also a subway station (Fullerton on red line) thats less than 10 minute walk that will take you back downtown (only 3 or 4 stops).