Can you explain how and when the downgrade happened?
A few days prior? On check-in? At the gate?

What were you told at the time?

What date did you fly? Was it one of the days the 738 did the route?

Thanks for the details.
NZ105 16:05 17:40.
QF583 19:55 21:50 is the last SYD PER flight of the day. Most days there are 8 flights.
(Last MEL PER flight leaves at 20:30)

What did QF (NZ?) tell you & when?
Any options given?

It is possible the Original Poster purchased a business class ticket AKL-SYD-PER at the 'usual price' but with the SYD-PER sector in economy.

I just made a dummy booking and it was quite easy to find this circumstance, and it isn't all that obvious that the second sector is in economy - especially since the price is unchanged from options on the same day where both sectors are in biz.

For the OP, what is the letter code on your e-ticket for the SYD-PER sector? That will tell us a lot about what has happened.

I produced this composite screenshot to show the dummy booking I made earlier - the red boxes are added by me and highlight the economy cabin on SYD-PER on this 'business class' ticket:

Thanks. That may be the problem. The fare class Sydney to Perth was described as "V" when the ticket reached me four days after I booked it. There is no warning of this downgrade on Air New Zealand's website and the box which you highlighted in red did not appear on my ticket. Do you know if this is a recent addition? At best, this is deceptive advertising and at worst, it is breach of contract. Another galling factor is that I could have bought a guaranteed business class ticket with Virgin via Melbourne for $100 less.

Unfortunately, it is probably best categorised 'caveat emptor' as you agreed to buy this fare, with those details - and I doubt you have any recourse.

Legally, I doubt there is anything you could do - try 'Fair Go'? Maybe those of a legal inclination can provide their thoughts if you want to pursue this....?

Treat it as a (painful) learning experience to be fastidious in checking details before pressing 'buy'.

The red box was added for the image - it is not present on the website.

It would seem highly likely you've simply not fully read the details of the ticket class or fare before buying it, so it's certainly something to be aware of of before clicking the buy button because flights on BP on NZ metal the whole way are around the same price or cheaper.

This is not a "downgrade" as such. It certainly is listed as economy on the website, and is consistent with Air NZ notifications and text won other partner airlines when you book a ticket that has a different class of service on a partner airline.

this may not always be true...my search for Nov had the direct Air New Zealand AKL-PER flight one way in biz significantly more expensive than options with a QF domestic biz sector.

To add to this looking at the fare guide and rules both J and V are used for Australian connections. J can be used for business on Qantas when there is availability - if there is no availability you'll be booked into V.

The price is the same for AKL-SYD-PER regardless of whether you're booked into J or V.

The Air NZ website says if you're booked into V and says you'll have economy on the QF flight. If you're booked in J there is no mention of this.

I remember looking at the Qantas site previously and seeing 2 stage flights with the 2nd in economy and costing the same as a full business class fare. I had to do a double-take. I know they charge business class rates for award seats even if the longest segment is in economy and you have a 1hr flight in 'business'. It's a crap redemption but I was shocked to see the same translated to revenue flights.

Anyway, it's worth taking note of the pop up boxes when they appear and reading them thoroughly. Especially with this Qantas partnership. I don't recall seeing that with the VA partnership.

I have the same problem - booked flights to Dallas with a colleague - he booked 5 minutes before me, Got J all the way - including domestic United. When I booked in J, only offered Y on one of the domestic legs and J on the other - price exactly the same. Told by NZ that United only release 2-3 seats per flight for tied fares with NZ and once they are gone, they are gone and defaults to Y, despite being the same price. It is hard to see if you don't look carefully when booking, but it is there. I think that is likely what has happened here. It looks like a J booking all the way until you look at the ticket - it is the small print, but it can be hard to see.

Yep. When booking J for any multi leg trip, I always check the details to see if there is mixed cabins in there.
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On United, they were selling $6k return business class fares to LAX... That being return business to Australia and then return Y to LAX! No thanks!
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https://www.qantas.com/fflyer/dyn/pr...4-october-2017
But the QF fare booking may not map 100% to NZ

Am sure you will look carefully next time, or not fly a codeshare

I don't understand how it's even legal to charge business class fares for economy flights? Doesn't make any sense to me.