Assign the phone multiple DNs (1001, 1002, 1003 for example). After creating the pilot point (1000 for example), go to Hunt Group configuration in CCM admin, choose the pilot point you created and add members. In this case, click Add Member and choose the User Member Information at the bottom of the page. This will be the attendant console user that you created and the line number. Add a member for each line that you created on the phone. Now when you call the pilot point and the first member (line) is busy, it will try the 2nd, 3rd, etc.