I am applying for I-130 for my spouse 20 months before and I checked to USCIS websites on Monday I got confirmation that the status now changed to post decision activity and they have mailed us but we still haven't received it. Can you please advise me what’s the meaning of this? it said that I am approved. Understand that learned from everyone here that the next step is will go to NVC then interview? and when my spouse face the interview approx (time)? Thank you all for your kind advise?