I can tell you that the FFR team coordinates closely with the Graduate Society in sending out invitations to accepted and pending candidates. The intent is to invite candidates that already have an offer or very likely to get one. While we do our best to balance being inclusive and not missing candidates that will get an offer, it is still a prediction. Every year one or two candidates that we invited do not get in and we usually miss one or two that did get an offer. It is an imperfect process.