Snom m9 DECT Administrator's Manual page 22

snom m9 DECT Administrator Guide
3. Click the Behavior tab of each Identity, and set the Allow Line Switching setting to on as shown
below:
The handset displays the display name/username of the first registered Identity in order of priority 1-9.
Incoming calls to any of the configured SIP accounts will alert the handset.
For outgoing calls, use the dial format of <Identity Index> * <Number> for selecting an outgoing line:
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