which sororities have made their big drops?

Every sorority has a different number to cut from RFM and no one outside a particular chapter would likely know what that number is, so we can’t say with certainty that XYZ sorority does its harshest cuts before pref while ABC does them after open house. However it’s safe to assume chapters are looking a lot closer at each PNM from this round and being more thorough because any PNM they invite back to pref is somewhere on their bid list and could potentially end up their sister. So if you end up with an invite to pref it means that chapter really likes you and truly can see you as a sister.