"有人说EB1B需要在递交485后为原雇主工作180天才能离开?" is true when "有人说 485等待期间也可以换工作,只要工作性质不变就可以" is true. There is a AC-21 rule if the 485 is not decided in 180 days, you can safely change to a similar job after the 180 days. Some people have to change job earlier than 180 days, and then if the 485 is not decided after 180 days, then he's safe; otherwise he's in trouble.