Mitel 6867i Administrator's Manual page 467

MITEL WEB UI
1. Click on Advanced Settings->Global SIP->Advanced SIP Settings.
2. In the "BLA Subscription Period" field, enter a value, in seconds, that the phone waits to
receive a BLA subscribe message from the server. If you specify zero (0), the phone uses
the value specified for the BLA expiration in the subscribe message received from the
server. If no value is specified, the phone uses the default value of 300 seconds. Valid
values are 0 to 3700. Default is 300 seconds.
3. Click Save Settings to save your changes.
USING A BLA LINE ON THE IP PHONE
If you have either a global or per-line BLA configuration, and you want to share a call on the
line with a BLA group, you need to press the Hold button before sharing the call with the group.
For example, if line 1 is configured for BLA, and you pick up a call on line 1, you must press
the Hold button to share the call with the BLA group.
Operational Features
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