Designating Specific SP Line Key to Handset for Answering Incoming Calls

[Charlemagne]

With my OBi1032, I want to control which line key is engaged when the handset is lifted from the cradle to answer an incoming call.  I've found no documentation on this.

My configuration is:

SP1  GV
SP2  Callcentric
SP 3  active SIP account

The non-GV accounts are for inbound Caller ID, and are registered to forward when my GV number is called.  All three lines ring simultaneously, but the handset consistently connects only to SP2 Callcentric, and cannot be easily diverted by manually depressing a different line key while ringing.  I want SP1 to be engaged when the handset is lifted to answer an inbound call.

Any help would be appreciated.

Thanks.

[SteveInWA]

Already answered.