Connecting flight query

Qatar are lying to you.
This matter was settled in the Gahan/Buckley v Emirates case in the Supreme Court.
Part of the Judgement, that in bold type is the 1st and 2nd parts of your legal arguements.
5. The Court of Appeal allowed Miss Gahan’s appeal and dismissed Emirate’s so that compensation was available for both legs in both cases. The Court started with the basic proposition that:
‘… where a carrier provides a passenger with more than one flight to enable him to arrive at his destination, the flights are taken together for the purpose of assessing whether there has been three hours or more delay.’ [73]
6. Accordingly, what counted was the delay in a passenger reaching their final destination. This was based on EU jurisprudence from Sturgeon v Condor Flugdienst GmbH [2009] ECR 1-10923 (C-402/07 and C-432/07), and from Air France SA v Folkerts [2013] (C-11/11), in both of which the Court of Justice for the European Union (“CJEU”) held that compensation under Article 7 of the Regulation was to be quantified by reference to the delay in arriving at the passengers’ final destination. In the case of directly connecting flights, a passenger’s final destination was the destination of the last flight (Article 2(h)).
Jurisdiction under the Regulation
7. The Court went onto reject Emirates’ second argument that the Regulation did not apply to flights operated by non-Community carriers (such as Emirates) outside of the EU. The Court considered that the Regulation took effect:
‘… when the carrier is present in the EU and it imposes a contingent liability on the carrier at that point. The liability may never crystallise but if it does do so, it will crystallise outside the jurisdiction.’ [76]
8. The basis for jurisdiction over non-Community carriers under the Regulation was, contrary to the submission on behalf of Emirates, territorial in nature [77]. It was sufficient that the first of two connecting flights departed from the EU. There were two reasons for this:
(a) the activity outside the EU was not relevant to jurisdiction, but to quantum. The Regulation applies to non-Community carriers because they use EU airports. Measuring delay by reference to connecting flights is simply the best way of measuring inconvenience [78]; and
(b) the decision was supported by the case of Holmes v Bangladesh Biman Corp [1989] AC 1112 which suggests that place of departure, stopping place, or destination are sufficient to avoid breaching extraterritoriality [79].

Those are articles written by journos?
This is the law according to the Supreme court:
5. The Court of Appeal allowed Miss Gahan!!!8217;s appeal and dismissed Emirate!!!8217;s so that compensation was available for both legs in both cases. The Court started with the basic proposition that:
where a carrier provides a passenger with more than one flight to enable him to arrive at his destination, the flights are taken together for the purpose of assessing whether there has been three hours or more delay; [73]
6. Accordingly, what counted was the delay in a passenger reaching their final destination. This was based on EU jurisprudence from Sturgeon v Condor Flugdienst GmbH [2009] ECR 1-10923 (C-402/07 and C-432/07), and from Air France SA v Folkerts [2013] (C-11/11), in both of which the Court of Justice for the European Union (!!!8220;CJEU!!!8221;) held that compensation under Article 7 of the Regulation was to be quantified by reference to the delay in arriving at the passengers!!!8217; final destination. In the case of directly connecting flights, a passenger!!!8217;s final destination was the destination of the last flight (Article 2(h)).
If the flight started in the UK and finishes outside of the UK on a different leg, it is the whole journey that is considered in respect of regulation 261/2004. I think this is clear cut and unambiguous.
I welcome the counter argument

Say the passenger left the EU on time and arrived at Dubai on time but then the flight to Sydney was delayed by 6 hours upon arrival (their final destination) they would not be due 261 compensation.

Thats because the second flight is a none EU airline, departing from a none EU airport arriving at another none EU airport. No part of the delay occurred in the EU so no EU261 compensation.
Is this not covered by point 5 and 6 of the Supreme Court ruling shown above?
Perhaps yet another grey area that needs a legal precedent set?

We will have to agree to disagree.
Your link is to MSE's interpretation (and how often have they stated incorrect facts with regards to 261/2004?)
I can see nothing in the CoA determination (my apologies for saying it was SC in error) that differentiates where the delay actually occurred?
Again point 5 is pretty clear cut to me.