Oops made a typo ZKNHB - Flight is 29 August.
My outbound flight is on 24 August on the 789. This was originally OKU as well, but this was swapped a few months ago.
I just had a look on expert flyer and there are not many seats sold in any cabin on NZ124 MEL-AKL - I do hope the equipment is not downgraded to an A320/1 as ExpectTheUnexpected said above. That would really ruin my day!