Yealink CP860 User Manual page 131

Configuring BLA Feature on the IP Phone
You can share a BLA number on two or more phones. For example, phone A registers the
account 14019833020 and assigns BLA number, phone B registers the account 10462190020
and assigns BLA number, phone C registers the account 14755608020. Phone A and phone B
share the BLA number 14084588327.
To register account and configure BLA feature on phone A via web user interface:
Register the account 14019833020.
1.
Click on Advanced, and then select Draft BLA from the pull-down list of Shared Line.
2.
Using Your Phone with SIP/Cloud Account
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