I have two analog lines and two IP712 sets attached to a 7060. The two lines are configured as SLAs and have been added to the two phones. The appear to operate as expected for outgoing calls and outbound calls can be placed on hold and picked up from the other phone. Inbound calls however do not behave as expected. The phones ring, but the call does not appear on the SLA line buttons. Instead, it shows as ringing in on the extension appearance buttons. When you pick it up, you can place it on hold, but it is inaccessible from the other set.
I suspect this is because the two phones are in a Ring Group that is referenced in the Trunk settings. I tried removing these, but then the calls do not ring in at all. I suspect I must be missing something simple?