The Early-Bird is optional and it's free -- it's a chance to come out the day before the BTM (Friday after 6pm) and set-up your system, pick your table and get some game action in before the BTM starts.  Attendees of the Early-Bird must vacate the Abattoir by 11pm, if however you wish to stay-over from Friday to Saturday, please check this box.  Stay-overs are an additional $10 and buys you fragging rights till you drop, a warm, hard floor to crash on and a crappy breakfast of cereal, coffee, juice and gruel; essentially, for $10 more you turn the BTM into a two day event -- a bargain.