I suspect I would either be trying to throw drugs at it (extra caffeine) or maybe setting an alarm for 7, grabbing a quick shower and food, and having evening socializing. I don't know if that would work for you, or whether having plans with specific people for slightly late meals would help (e.g., someone who will knock on your door at 7:20 and then go somewhere with you for food). I can't offer myself, because I won't be at the con.