That's right - my 318k capped multi city reward booking has 1 leg in Economy and 2 in Premium Economy. All the rest are in business.
My partner has exactly the same flights, but just all her seats are business (so essentially I lose out because not all mine are in business but yet I've paid the same amount of points, but less tax - which I'd be willing to make up for should I find business seats).
Considering it was capped at 318k after picking the 5th leg and I've met all the conditions of the OWA - if I was able to find a free business seat on the PE legs (I'm not too fussed about the Economy leg as that's only 2 hrs) and call up to change to business - I 'should' only be charged the 5k points change fee + taxes, and not the 55.8k points + taxes that was quoted to me?