Can anybody tell me if AC 38 PVG-YYZ is same plane service, or is there an aircraft and gate change in YVR? Do the YYZ bound Pax clear customs in YVR or YYZ?

Finally, my sister-in-law, who is 6+ months pregnant and just at the legal limit of being able to fly is travelling on 4/11 and I would like to try and arrange for the AC Concierge to help her with her trips to and from the gates where applicable. Any suggestions on how best to arrange this.

Thanks

DF