If it makes you feel better, I haven't been home 4 and a half years, and since I made it so far I'm not ready to jeopardize my AOS at the last minute. From my lawyer's experience, AOS interview notice can actually arrive 2 weeks or less before the interview. For me it can be any day now. I'll just hold on for a little bit longer, and then I'm going home for a month.
By the way, I'm on F-1 visa and I'm hoping to get an interview before the next school quarter starts because it would be like 3 times cheaper to register for classes, then what I'm paying right now. Since you are both on F-1 visa, are you both going to be registered for the classes until the interview?