Not sure what version of CUCM you are using or what model/type of phone. On the line configuration for the phone, you will see a section called "Forwarded Call Information Display on Device SEPxxxx". These options can be checked to control what is displayed on the phone when a call is forwarded to it. It affects all calls forwarded to the phone.
The default is to display "Caller Name" and "Dialed Number". So, if you set it to Dialed Number only the display on the phone would be:
Forwarded
For 1234
If the original called number (i.e. branch office number) is not answered.
HTH.
Regards,
Bill
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