"adding" to my BEV Sub? What do I need?

[whitecastle]

I am a current subscriber with a 9200. Can I maintain my current sub, and just "add" what I am missing? If so, what do I need? Can having a valid sub make this process easier?

I'm looking for the easiest solution. If that means hooking it up to my computer that's fine too.

what are my options?

Thanks in advance for sharing your knowledge!