If needed, admins can unshare a review packet after a manager has sent it to the reviewee. Notifications are not sent to the reviewee or manager when unsharing.
Navigate to Admin > Performance > Reviews.
Select the review cycle.
Enter the Share phase and find the reviewee who needs to have their packet unshared.
Select the ellipsis (...) to the far right of the reviewee's name and then select Unshare reviewee packet from the drop-down menu.