I-485 approved while abroad with AP. Will this complicate passport/N600 process?

[warura 0]

GoodDay. Hopefully, someone knows and can help me on this matter.

 

I'm a US citizen and my son (a minor 15y) got I-485 approved and we are still abroad. We have been using his Advanced Parol without a problem a couple of times to visit family and manage paperwork abroad since my father-in-law passed away.

 

I have read that he can use the AP or the GC if we can get it delivered on time to re-enter the US, but that's not my concern.
When we started the I485 process the preparer we hired stated, that once he was approved, we needed to file for the passport/N600 and not use the GC to travel abroad. Would this complicate the process for his passport/N600 or why would he mention this? We will have to re-enter with the new info on hand (GC if it gets delivered before his return), and apparently, it depends on the officer on how he registers his entrance, as AP or GC.

[warura 0]

anyone? 😕