Re-do the descriptions on the Pages in the Telephone Tab
Front Desk
As an example: this is the verbiage that is written on the call groups page.
"Assign devices to this group, have them ring simultaneously or in a cascading order, and set each device's ring duration and ringtone.: I just spoke to someone in the phones who agrees that those directions are not accurate because you cannot adjust the way that the phones right on that page.
The description in the call groups page is accurate. You can use the sliders to change when a phone in the group starts/stops ringing. This does not apply to mobile app lines, as those ring start times are controlled by the native application. The ringtone is set for the entire group and not on an individual phone basis.