Top houses don’t COB

Last year the Panhellenic form for COB (which was still posted on their site 2 weeks ago) has Chi O listed as one that was participating. So I’m not sure what you said it totally accurate.

Aphi didn’t participate in cob this year. They have all the girls they want :/

COB happens more often than anyone realizes in ALL chapters.

Any sorority can COB when they go below Total, which is the maximum allowable membership for a chapter set by panhellenic every year after Bid Day. Eligible chapters can Continuous Open Bid to get up to Total and can do it at any time after bid day without an announcement that they are doing it. Chapters with only a few spots to fill already have in mind who they want and will offer bids on the DL and then register them with panhellenic as new members. A COB announcement isn't necessary and would be misleading.

All chapters lose members from December graduations, transferring schools, leaving for family or personal issues, or deciding to go inactive for whatever reason. It happens. COB does not mean there is a membership issue and ALL chapters do it. Chapters that graduate a bunch seniors in December are more likely to announce they are doing COB because they are actively looking to fill the spots, and sometimes their nationals have a target membership number for them so they must attempt to reach and maintain it.