I would imagine KF and staff really like the early signing period. They can get most of their commits signed on before the bowl games, than check the transfer portal before spring semester starts. By the time the first signing is done and transfers lined up at the beginning of the semester, the traditional signing day becomes something of an afterthought for tying up loose ends.
Keeping commits engaged through to the February signing day burned up up an unnecessary amount of the coaching staff's time that could be devoted toward player development and planning for spring training.