^^no you don't positively need recs. You can not sign up the same day anymore. The cut off is, I believe, after orientation now which is a couple of days before recruitment begins. If you are the total package as an upperclassmen you can get a bid. Here is the story of a junior that went through last year and was unsuccessful.
http://www.greekchat.com/gcforums/sh...d.php?t=122900. If chapter ranks means tiers no they don't change.