20 songs for an audition sounds rediculous. IMO a band is trying to assess whether you can play and have the right chops for them, and they can suss that out in a matter of 3 or 4 songs.
Maybe when they landed you with the 20 tracks, it would have been wise to tell them you have a life outside of music that has to be tended to, and 3 or 4 would have been more realistic, given the time restraints in your life