Yealink SIP-T48G User Manual page 171

(Optional.) Enter the always forward on code or off code respectively in the On
3)
Code or Off Code field.
You can also activate always forward for all accounts. Do the following:
Tap the All Lines soft key.
1)
The touch screen prompts "Copy to all lines?".
Tap OK to accept the change or Cancel to cancel.
2)
If you select Busy Forward:
b)
Tap the On radio box of the Busy Forward field.
1)
Enter the destination number you want to forward incoming calls to when the
2)
phone is busy in the Forward to field.
Basic Call Features
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