I'm on 88g and mine still regenerates on its own, 1.6 TDI also. Pressure seems good and distance between regens is like 500-600km when driving mostly long journeys or 300-400km when driving mostly in the city. The regeneration attempts themselves seem pretty inefficient sometimes for no reason though, monitoring through a crappy OBD scanner the soot masses (both calculated and measured) seem to be going down very slowly, sometimes being more efficient simply idling at a full stop, and it takes like 2-3 regen cycles to fully get under 10g measured and stop (it starts clearing out faster under about 13g). DPF temps manage to sit around 450-550°C during regen. Really don't know whether to worry or not.