They absolutely said that for OS the use of an ECA was based on the high crossover rate within the trial. That is data from the trial.
For PFS, they claim it is based on the new science of psPD and immuno agents. Problem is, this will be viewed with skepticism as they already knew the PFS endpoint was futile. Had the IA in 2015 shown the designed PFS endpoint was a success, they would not have changed it?