I think 'The Five' and its multi-host format led a lot of former Kelly viewers to watch other programming. Not Maddow, other things. Same when Hannity moved to 10.
Ingraham will bring her radio fans in as well as some of Kelly's viewers who went elsewhere while Hannity will retain his audience while bringing back many of those who stopped watching when he went to 10.
Carlson at 8 remains a weak spot, but FNC is likely to extend their lead as the most watched cable news channel as a result of these changes.