人在中国申请EB1A

One of my friends applied EB1A I-140 when he was in US, and it was approved. But he had J1 visa and he has to go back to China for 2 years. Now it has been one year. Can he apply the documents similar with I-485? It seems like I-824 form? If he can, does he have to apply that till he stays in China for technically two years, or the two-year contract could be valid when he gets the green card? If he can, what kind of documents he needs? Sorry to bother you with so many questions, but his case is kind of special. I appreciate your help.