[rondeo]

'Natural burn' There is a catalyst (platinum) which enables a burn of carbon at a lower temperature than would normally be required. It is continuous at normal operating temp.

'Controlled burn' happens frequently (every 300km or so depending),
with injection of vapourised diesel ahead of the DPF, because the catalytic effect is insufficient.

'Dealer burn' temperatue is no higher than normal regeneration, which is around 600 degrees C. It normally happens frequently at a standstill and is quite noticeable with thumping noises and changed exhaust note.

My car has done 280 000 km and the differential pressure has hardly changed since new, but yes, ash is accumulating. Depending on the oil etc.