It is trying, but good luck
Your best bet is to get someone who can "work the system". I know that we'd all like to think that getting a short-sale done is like ordering a whopper, but it's not. There's dozens of people involved, and the banks have their own prioritization systems for figuring out how to move the properties off the books. As mentioned, every deal is different, but I recommend getting your attorney or agent to get the paperwork done so your own proxy can get the story straight from the horse's mouth, and call citi directly. It might not speed it up, but at least it removes the layers between who's talking and you. Hopefully, your agent has done this before!
Short Sales take a lot of patience, but if you can wait, you have an opportunity for a great deal. Just take that into consideration when first making the offer.