In my professional experience DACA cases have been taking around 4 months. But there is no set timeframe for adjudications and by previous communications with immigration officers they can take even 6 months.
What kind of case is it? you can look at the processing case times for any case on the USCIS website. Case processing depends on that and if your case has all the evidence they need along with other factors. What they told you to check back in one month and the 6 moths is standard USCIS responses to telephonic inquires. Good luck.
There really isn't anything you can do to rush a DACA case. I have cases that were filed at the same time and resolved months apart. If yours needs "extra review" there is no telling how long it will take. Since this is a new process there isn't much history to go by.
Your DACA case can take up to six months to review, and since the process is fairly new, there's no history for a practitioner to use to give you a different time frame. You need to remain patient, but vigilant. Check your online status on USCIS's website and check their table with processing times. You need to wait until at least March before you send an inquiry.
Please remember this is not official legal advice, and this is no way establishes an attorney-client relationship. For a free 15 minute phone consultation please call 972-638-7207.