Dear PJIANG,
I first came US hold J-1 as Chinese citizenship, during J-1 peried I got Canada GC, after J-1 program I moved to Canada. After live in Canada 5 years and changed Canadian citizenship, I moved back to US hold H1b, now I am I485 pending(based on NIW I140 approved). Do I need J-1 Waiver from China? would you mind tell me how to do that? thanks