They didn't admit, that there is a difference between the Samsung and the TSMC processor, of course. But they admitted that I have a problem with my iPhone, that causes low battery usage time, whatever it is. And as long as that problem exists - (and we know, that it always exists with a Samsung chip based iPhone) - they will exchange it for me until I am happy with it.
And after the 2nd or 3rd time of exchanging the device, I can have my money back, but I think that has a legal cause here in Gemany: the manufacturer is allowed to correct deficits 2 or 3 times and if the deficit still exists after that, then you can bring it back and get your money back, irrespective of the return period.