snap bid

I keep hearing of this and COB, can someone explain?

A chapter can offer snap bids basically between now and tomorrow. If they come in under quota for whatever reason, they can call girls who participated in recruitment but haven't committed to a sorority and offer them a "snap" bid. There's a chance that can also happen after bids are given out but I'm not 100%?

It is usually associated with houses that are lower tier but my friend at UF said one of their top houses somehow screwed up last year and had to snap bid like 1/3 of their pledge class. It could happen in theory to a top house if they cut too deeply at the beginning of the week but girls didn't rank them after pref and were matched with other houses. That is NOT common so don't count on it!