US citizen. Us-inbound flight arriving at YVR E or B gates (from flightaware) around 11am, followed by an international flight at 13:45pm.

1. I won't have the outgoing boarding pass and have to pick it up at the D gate. The previous thread mentioned that it's ok to show the itinerary. Is this still the case?
2. I understand that I have to follow the "International Connections" sign and go through CBSA. However, it seems that there is an additional security after CBSA, according to the terminal maps. Do I have to go through the security check or the One Stop Security program will work here?
3. Would the process be different if I arrived at E or B gates?

Thanks for your help.