It takes about a month - you have to call uscis more then few times to get info on things like that - depends who you talking to really - its like that here in the usa - one person could tell you everything is ok but when you call again to confirm that some other person will tell you nothing is been done .....so always call more then few times ...system is broken and lots of people working for uscis don' give a f..k about you or your problems ....they just don't care ...as long you understand that and how it works in the usa you will be fine ......