Thanks a lot for the document, I’ll go through it carefully — even with the bad translation!
Regarding the DOC, the front part of it was heavily clogged, so we decided to replace the whole DPF assembly including the DOC. Unfortunately, we couldn’t determine the exact cause, but it might have been due to incomplete regenerations in the past or oil contamination during the engine swap (the engine and injectors were replaced a year ago).
About the temperature: I’ve seen the DPF temp reach 800 °C during regen attempts, but the actual cutoff doesn’t happen at that point — in fact, when the regen cuts off, the temp is around 580 °C. So maybe the peak temperature isn't the trigger after all. I haven’t found a consistent pattern between temp, pressure or speed and the regen interruptions.
Eventually the DPF did regenerate properly after the last trip, and the saturation dropped to 16%. But I’m still trying to understand why so many regen attempts get aborted before that.