If the I-140 was turned down, there might be some problem. Of course the minor one is that the processing fees for I-485, EAD, AP. You could not apply for an F1 visa any more.

以下是引用e-bunny在2004-9-22 17:35:53的发言：
really? actually, I've been thinking of changing majors (going back to school...) lately even after I have been a postdoc for a year now...

Thanks!

You can not go back to school and change a major before you get GC fully.