Yealink CP860 User Manual page 127

Click on Advanced, and then select Shared Call Appearance from the pull-down list of
2.
Shared Line.
Click Confirm to accept the change.
3.
To configure the shared line settings on phone B via web user interface:
Register the alternate account 4603_1.
1.
(Enter the primary account 4603 in the Register Name field.)
Using Your Phone with SIP/Cloud Account
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