Do I have to apply for Advance parole as an H-1B holder with an I-485 pending, when I am not sure that I can get an H-1B visa to reenter the country once I travel abroad?

We suggest applying for Advance Parole and getting it before you travel abroad to ensure that you can re-enter the U.S. You should take your Advance Parole with you, but try to apply for your H-1B visa first. Your Advance Parole will serve as an assurance, if your H-1B visa application is denied.