Hello fast_gc_seeker,
see below, this is from immigration-law.com archives,i read this long back.
hope it helps, Good luck.
09/10/2005: EB-485 Advance Parole Travellers and Consequences of Returning to the U.S. Without a "Valid" Advance Parole
Nowadays, we see some victims of EB-485 travellers whose I-485 applications are denied for having returned to the U.S. without a valid advance parole. Such travellers include returning in nonimmigrant status other than H-1B/H4 or L-1/L-2 or without a nonimmigrant status such as a parole not based on advance parole. The law is clear in this area. The EB-485 applicants have only two means to travel without abandoning pending EB-485 applications. One is a valid advance parole and the other is a valid H-1B or H-4 or L-1 or L-2. All other entries in other nonimmigrant status or on parole not based on a valid advance parole will be considered "abandonment of EB-485 applications," and the pending EB-485 applications may be denied by the USCIS. Travelling with a "valid" advance parole includes "approved" advance parole at the time of departure from the U.S. and "valid" advance parole at the time of returning to the U.S. If one departs pending application for advance parole which is subsequently approved while the alien is outside of the U.S., returning on such approved advance parole may not comfort with the statutory requirement for travelling on a valid advance parole and such EB-485 applications can also be denied. It is thus prudent that the EB-485 applicants travelling on Advance Paole should schedule international travel leaving a sufficient time to return to the U.S. before expiration of Advance Parole. There are episodes of some of these EB-485 travellers who tried to return to the U.S. after expiration of Advance Parole because of exigent circumstanstances like flight delays or certain natural calamities during the journey and have been paroled in on the humanitarian concerns or other grounds of so-called public interest. Such entry may not save the travellers from potential denial of the pending EB-485 applications. Watch out. People travelling on Advance Parole often fail to distinguish the two issues: One is whether one can reenter the country after the trip, and the other is whether such reentry will still be considered abandonment of EB-485 applications. These are two distinctively different issues. The fact that such travellers were allowed to retun to the U.S. by the immigration officers at the airport on a ground other than a valid H or L visa or a valid advance parole does not effect that such travel will not result in abandonment of the pending EB-485 applications.