Originally Posted by
Top of climb
MSC only applies to a single checked baggage "journey". In this case the OP has the option to break the journey in SYD because they have to uplift their checked bag in SYD and drop it off again with QF. While it could be a single journey for MSC purposes - eg if the first operating carrier tagged the bag all the way through to the final destination such that the manual intervention of picking up and dropping the bag off at the transit point did not constitute a break in the journey, because the tag is all the way through - it is also capable of being broken into two journeys in which case the rules of the operating carrier would apply to each "journey".
NZ and QF have an interline agreement, and all news reports indicate that the codeshare agreement has "easy baggage transfer" which would indicate to me that if booked on a single PNR, you're getting a single bag tag - meaning MSC rules apply.