As others have said, it's all who you get. I recently had one done by CX in Hong Kong in about an hour and a half. Most of that was probably because I left to go eat lunch or I am sure it could have been sooner. I have had AA take literally days and still screw everything up to the point that I took the ticket to BA. In all fairness, though, AA has done quick ones for me as well. The Wellington thing, frankly, sounds like incompetence and laziness to me. There is no reason they would have needed to see the AA flights. Build the damn ticket, leave it as open, and just go off the original PNR for the reservations.