If I have a ticket that has been assigned to someone in a group, and I want to assign it to someone who has yet to be added to a group, there appears to be no way to remove the group from the field. You can change groups, but you can't search for or enter a user that has no group. If you start out with the ticket assigned to a person without a group, then you can add the group, but once you do you are again stuck.
Does anyone know of a way to remove the group and search for, and assign, agents who have not yet been assigned to a group?