My wife and I went to interview this morning, with our attorney. Other than going over the I-485 forms, he only talked with the attorney about our other AOS applications under EB. He was a very talkative person and had a lengthy conversation with our attorney about how stupid things were going in immigration offices.
After all these unrelated conversation, he said he could not approve the case right now, and he gave us a lengthy empty reasoning that we couldn't understand. In brief, he talked about some personals on vocation and things were solve and his boss was off and his boss needed to do something that he did not articulate for some reasons. He said we should not worry about anything but just wait 1-2 weeks to receive the letter (I assume welcome letter), if not, try to contact them.
I asked especially about name check process, and he confirmed that it was complete but he said he saw something "duplicate name" which he said not any problem. It sounds silly but he did not tell us exactly why he was not able to approve the case; just something he needed his boss to look at. Our attorney did not want to insist more there, rather, to wait for two more weeks before starting any further inquiry.