Avaya T3 (IP) Comfort User Manual page 17

Familiarize yourself with your telephone
Putting the telephone into service (T3 IP only)
Logging off from telephone
When you want to log off from the telephone again:
Press the "Menu" function key.
Scroll to the Log off menu item.
Confirm your selection. You are now logged off from this telephone. Another
user can now log on.
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