Generally the biometrics appointment is about 2-5 weeks after filing the application.
Once the appointment notice is received, he can attempt a walk-in before the official appt. date.
How much time has he been spending outside the US to manage this business? 3 months/year? 6 months? 11 months? If he's spending too much time he might have bigger problems with his green card.
PD: Jan 2003 (EB3 rest of world)
I-485 Approved: July 2007
I am a layman, not a lawyer. What I write here is not official or professional legal advice. In addition, my answers on this forum are specific to the scenarios discussed in each thread and should not be generalized to other situations.