Originally Posted by
Top of climb
In my experience you don't have to be in possession of an onward boarding pass to clear transit security so you should be ok (assuming you have no checked bags or they can be interlined).
Haha in the case of my friend on EY from SIN yesterday (all on one ticket in conjunction with NZ), he checked in online for the EY flight and had his luggage interlined onto NZ136 at SIN. Someone forgot to/didn't check him in on NZ136 so they obviously weren't able to board when they were in BNE. They couldn't get rechecked onto NZ136 so they got an upgrade on NZ734 (772) and spent 5 hours in the lounge..
So no, you don't need an onward boarding pass.. Just make sure you get a boarding pass/you're able to get a boarding pass or else you'll be stranded!