What are our options for premium economy upgrades from Perth to London using Asia Miles or Altitude Points?

I have 39000 Asia Miles and 79000 Altitude points. We are hoping to upgrade an economy to a premium economy one way flight from New York back to Perth in September 2017. Can anyone suggest how many points we will need to do this and which carrier would be the best option?
thanks,
Liz

Go Cathay via HKG. Not the shortest distance for that trip, but you have AsiaMiles so Cathay makes sense. Bit shorter via Singapore, but won’t save you any points.

You will need to be travelling on a fare that can be upgraded (Y, B, H, K and M). And you need availability.

If it was me, I would check some options on Cathay’s website and then book over the phone with them, making sure that the flight I was booked onto had availability for a premium economy upgrade. I would then nail the upgrade at the same time. It would suck to book a flight and then find out that there was no upgrade availability. I expect this far out you’ll be fine.

A one way premium economy upgrade is 27,500 AsiaMiles (i.e. you have enough for two pax).