My son's I-485 was approved, but he hasn't received his plastic card yet. We are planning to travel to our home country at the end of the year, so if we don’t receive his card before then, we’d like to take an infopass appointment and get his passport stamped at the local office. Except for his I-485 approval notice and passport, what do we need to bring to the appointment? Do we need to show airplane tickets or evidence of why we need to travel? If somebody could share their experience, that would be great.