Assistance Required for Setting Up Ring Intercom with Bitron AN0002 and Existing Building Intercom System

Dear Community, I am in the process of integrating my Ring Intercom system with an existing Bitron AN0002 intercom handset and seek your guidance for an optimal setup. My current setup with the Bitron includes a blue wire on terminal 1 for speech input, an orange wire on terminal 2 for speech output, a brown wire on terminal 9 for lock control, and a green wire on terminal 6 as the common connection. In our building’s intercom system: The bell rings both downstairs and upstairs without distinction; ringing my doorbell activates the same connection. Picking up the intercom phone instantly connects me with the entrance, with no button press required for communication. The only functional button on my Bitron handset is for door opening, which I’ve managed to connect using Ring’s A cable. Given these specifics, I would appreciate advice on whether to continue using the A cable or switch to B or C cables for the Ring Intercom. Additionally, I request detailed instructions on how to match my Bitron’s wiring to the Ring system, ensuring full functionality of both communication and door control features. Thank you for your assistance.