I would take a close look into the DPF fuel doser. Leak and flow check it for starters. Excessive fuel entering the exaust can cause higher than normal DPF inlet temps which could cause the fault as well as the hot/ smoke due to the higher than normal temps.
Otherwise get hooked up and check faults and troubleshoot accordingly. If it still has the old doser with the bolt on heat shield, best replace it anyhow.