pref!

But my understanding from when I went through a few years ago is that if you attend all of your parties, especially if you have full parties every day, you will receive a bid. "Attending all of your parties" is obviously not true because girls who go to all of their parties have been cut. However, on preference round, if you have 3 chapters on that day, I am 99.999% sure that you will receive a bid from a chapter. It may not be your number 1 choice, but it will be a bid. By preference, chapters realize that any girl that walks into the room on pref round could be walking into their house on bid day and that's why the round is so serious.

From speaking with Pan representatives they said if you attend 3 pref parties and rank all 3 you WILL get a bid. However, i do not know the case if you're only invited to 1 or 2 parties (pretty sure the same goes for 2 parties though)