Upvote:3
It seems like a straightforward case and EU compensation does apply. Your flight has been cancelled so article 5(1)(a) gives you a choice between
Since 6 hours and 15 min after the scheduled time of arrival is too late to avoid paying compensation under article 5(1)(c)(ii) or paying a reduced compensation under article 7(2)(c) and unless they claim “extraordinary circumstances which could not have been avoided even if all reasonable measures had been taken”, you are also entitled to €600 under article 7(1)(c). Note that the clauses of article 5(1) are joined by “and”, implying that you are entitled to compensation even if you choose not to fly.
I don't see anything confusing about that and the other two issues, downgrade and “comparable transport conditions”, do not change anything to this. Specifically:
The clause about “comparable transport conditions” has little teeth, I think it's about preventing egregious abuse and not giving the airlines the option of choosing to pay instead of providing transport at all. The choice should be yours and by offering an alternative that brings you to your destination a few hours later on the same airline, they have almost certainly satisfied that.
I don't think the downgrade article has been tested much but I see no reason to think it means anything else than another cabin (e.g. economy instead of business). It has little bearing on the whole article 5-8 business and thinking you should get something on top of the usual compensation because there is a stopover when that notion is nowhere to be found in the regulation and the flight they offer really isn't that bad sounds like wishful thinking.
In fact the language of the regulation and especially article 8(1)(b) put a strong obligation on airlines to do the best they can to get you to your destination quickly even if that means using another route. But they should probably allow you to take a direct flight the next day or later if you prefer that.
On the other hand, the EUCJ made a mess of articles 5 and 6 in Sturgeon so maybe you can have a few years of fun in court and convince it to create a new compensation out of whole cloth if you are so inclined.