HEY SECMOM!
Let me emphazie this -- I can tell y'all what my personal understanding is of the polices at Bama but that doesn't mean I'm 100% accurate.
Panhellenic promises each PNM that if they go through the process in good faith and maxmize their options throughout, they will receive a bid from one of the Chapters they preffed. If she doesn't match before all 3 of those Chapters fills quota, she will be placed in one of them as a Quota Addition. Panhellenic will take the following into consideration when deciding which Chapter to place her in: see that no single Chapter gets a ton of Quota Additions while others have none; try to honor a PNM's priority list (i.e. #1, #2, #3); take into consideration where on a Bid List these PNM's fall.
HOWEVER, I'm pretty sure a PNM must have been invited back to and attend 3 Chapters on Serious/Pref night, the max number of parties. Now if a PNM was only invited to 1, this guarantee does not apply because in essence it would mean the Chapter had no say in the matter. It is supposed to be a mutual selection process afterall. If a PNM were invited to only 2, the odds are significantly better she will receive a bid from one, but not a lock. In both of these scenario's Panhellenic will do their best to place these women, but there is no guarantee. Yeah I know, that's kind of unfair because whose fault is it if a PNM didn't get invited to 3? I guess it comes down to the fact that Panhellenic tries to match as many as possible, but simply can't do it for everyone.
Also something to keep in mind, a PNM must have maximed her options
throughout the entire process. Meaning, if she were invited to only 7 Chapters for Skit Day/Round 3, she must accept all 7 (the max number for that round). If the PNM cuts one Chapter herself because she had no interest and only attends 6 parties, the guarantee no longer applies. Same thing with Philanthropy Day/Round 2 and the 11 max parties. I do not believe the guarantee is voided if she isn't invited back to the max in the earlier rounds. I'm pretty sure it only applies to Serious/Pref Night.
Again to be completely honest, I could be wrong about all or parts.