shishe
It really depends on a lot of factors. I have tried one day in Seattle, and I spent about five good hours in vain. The officers let me in, but when my number was call on, they turned me away informing me that they were busy and the my date had not been reached. This does not mean that if you try you may end up in vain, you find them idle and they have you do it. It all depends on how busy they are. From experience the Seattle office is always busy!