Originally Posted by FlyingAY

If pilot strike is the reason for the cancellation, then EU261 applies. CJEU judgment on case C-28/20 Airhelp Ltd v Scandinavian Airline System SAS makes it clear. The Court of Justice's reply is not merely an opinion, but takes the form of a judgment or a reasoned order. The Court's (CJEU) judgment also binds other national courts before which a problem of the same nature is raised. Thus it´s unlikely that the Finnish courts would rule against in similar cases.

In my personal experience AY has paid EU261 compensation accordingly, when delay or cancellation was caused by internal strike.