One of my friends came back to China in November and applied H1b in Beijing. his major is Civil Engineering.he is also a status of 485 Pending, with EAD and AP in hand. But he still choosed to apply for H1b and got visa easily. now he already back to America and no any trouble.
he prepared Company head letter,H1b approval notice with I-94 attached,6 months orginal pay-stab, bank statement,w-2 form, and all his I-20 in american schools.
Hope it is helpful.