Originally Posted by
Some person
Only the European Court of Justice can determine if strikes are extraordinary circumstances or not.
For now, that is not universally true. It may turn out that way, but it's not that way yet. National courts and administrative bodies can also determine what is and is not an extraordinary circumstance for purposes of EC 261/2004. Parties of concern could appeal a national ruling to get the ECJ to overrule, but until then it's not only the ECJ that can determine what is and is not covered under EC 261/2004. Unfortunately, pursuing the claim for this SAS situation in Sweden is likely to go nowhere unless somehow appealing it up to the ECJ, and even then there is no guarantee of the court siding with the consumers.
As I've noted earlier, the EC has provided indications that some strikes should not be considered "extraordinary circumstances", and that EC sentiment is likely to also be codified if/when EC 261/2004 is updated/replaced. By way of that, this kind of SAS strike would not be classified as an "extraordinary circumstance".