I live in Livonia, close to Detroit.
I changed from AOS to CP. I had interview in Jan 30 in Montreal. I got the green cards in mail in Feb 27.
Alincosma, when I wanted to do AOS we called and ask where to send all the forms and they said to put everything in one envelope and send to USCIS and write on the envelope Diversity visa or something similar. But when I read the instructions if I remember well, they were supposed to be sent to different addreses (I-485 one place, Work permit to another, etc). After the bed experience I had with the labor certification, slow, and they almost lost my files, I had to put the lawyers to call them all the time until they found my file, I decided I don't have patience anymore. But for your number it's enough time, just wait and everything will be fine.