AT&T MERLIN LEGEND System Reference Manual page 242

Features
Remote Access
Ringing Options
Signaling
Station Message Detail
Recording
System Access
System Numbering
If all QCC system operators activate Position Busy while an overflow call is in the
QCC queue, the call is re-routed to the original calling group and not to the
calling group providing Position Busy backup.
Remote Access users cannot log into a calling group but a Remote Access user
can call into a calling group regardless of the restrictions applied. When the call
rings at a calling group member's telephone, it rings as an outside call. A calling
group can be programmed to receive calls from Remote Access users to invalid
extensions. A line/trunk cannot be programmed for both Remote Access and
ringing into a calling group.
Abbreviated ring is not operable for calls to the calling group extension since a
calling group member active on a call is considered unavailable for incoming
calls. In the Hybrid/PBX mode, calling group members should program System
Access buttons for Immediate Ring.
A signaling button cannot be programmed for a calling group.
Calls to calling groups are associated with the first extension to handle the call.
If the call is answered by the calling group delay announcement device, the
extension for the device is recorded on the SMDR record even if the call is
transferred to a calling group member or to an overflow group. The timing
begins as soon as the calling group member or delay announcement device
answers the call. If the caller hangs up while when listening to a delay
announcement the call is associated with the extension of the answering
device.
Incoming calls to the calling group ring at Intercom or System Access buttons
on calling group member telephones. In the Hybrid/PBX mode, a calling group
member using a Shared System Access button to make or receive a call is
considered unavailable. However, the principal station member is not
considered unavailable and can still receive calls directed to the calling group
since use of a Shared System Access button does not indicate that the principal
calling group member is on a call.
If a person uses a Shared System Access button to join a call waiting in a calling
group queue, the call is removed from the queue and both people and the delay
announcement, if programmed, are connected.
Extensions for calling groups (the factory-set extensions are 770-791 and
7920-7929) are assigned and can be renumbered through System Numbering.
Group Calling 2-193