So what exactly do they intend to do??
It seems like a pretty cut and dry case here. You DPF is blocked and the car is triggering regen after regen which in turn is contaminating the oil due to the excess regen cycles.
The simple way to sort the problem is to change the DPF. Ho hard can it be for them to come to that conclusion? As the car is still in warranty then this should be replaced by Volvo.
I would keep pushing them to replace.
