Intercom; Forward Calls To Another Extension; Do Not Disturb - Panasonic KX-NT6 Series User Manual

This is the DEFAULT setting at the phone that will send
your busy or no answer calls direct to your mailbox.

Forward Calls to Another Extension:

When your phone is idle (leave the handset in the cradle) –

INTERCOM

This program will send your calls to another extension,
BUT any calls not answered at the forwarded extension
will be sent back to the original extension's mailbox, NOT
to the forwarded to extension's mailbox.

Do Not Disturb:

This feature will send your calls direct to your mailbox
without ringing your phone.
INTERCOM