What's With The Overnight Update--or---Where Are Donna and Carol?

Over the past two or more weeks, higher-profile Fox News Channel talent like David Asman, Page Hopkins, Kiran Chetry, Gregg Jarrett, Patti Ann Browne, and Lauren Green, among others, along with freelancer Darby Dunn, have been doing FNC overnight news updates instead of Donna Fiducia and Carol Iovanna. Whether Donna and/or Carol may be on vacation, or assignment, or ended up with a contract that was not renewed remains to be seen.