AT&T System 25 - Manual (Page 51)

Callback (Continued)
Display
Typical displays for Callback are
When you successfully complete
shown below.
a Callback request, the display
shows :
CALL QUEUED
When you receive the callback, information associated with the
originally-dialed number is displayed, preceded by “Q”. For
example:
Q95551212
If the request fails, the display shows:
QUEUE DENIED
If you cancel the request, the display shows:
QUEUE CANCELED
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