-No.
please advise. if he appeal can he leave during the appeal period?
-Yes. He had better file the I-485 Motion to Reopen/Reconideration (MTR) and justify himself in the cover letter based on the denial reasons. After he files the MTR (after USCIS accepts it), he can use the AP to travel. Talk to his lawyer about the MTR filing and prepare the documents carefully and he will be fine.