I believe the committee has already “cleared” a group of prospective students for admission, and it has been up to individual PIs as to whether students are admitted right away or after a campus visit. The official visit weekend seems to be mid-March.
Which PI were you interested in working with? Feel free to PM me; one of my close friends applied to UMich, was accepted, and recently declined the offer of admission. From talking to her, it sounds like the process is still rolling. Best of luck to you!