Originally Posted by olivier

The differentation between delay and cancellation of a flight is very controversial. According to german court decisions it depends whether the flight is definitively not carried out or the delay is so long, that it has the same effect as a cancellation.

According to LG Darmstadt a delay of 25 hours can still be a delay. An other decision of AG Rüsselsheim says a delay changes into a cancellation after 48 hours.

There are no strict rules. It depends on the concrete circumstances.