Good news.
Coz 1. your case is active; 2. you have chance to talk with IO face to face; 3. Even they ask more, you know what they want exactly.
Why are you so lucky being selected? The answers for my case (485 interview):
USCIS----"standard procedure"
Lawyer----"quality check"
IO who interviewed me ----"I DO NOT KNOW"
BTW, I am EB2.