The Perla One and Duplex use dH everywhere. Edit: I checked and they actually publish 4 values: ppm caco3, dh, fH, mmol/l. I do calculations with dh, but guess it work with the others if they are different by just a factor.
They also have two different service counters, one performed by the customer twice per year, and the technician one every second year I think. But maybe the intervals are different, could be 6 years for yours.
BTW is there any authentication for these routes?
And have you figured out whether the water consumption is blended water (actually used liters in household) or fully 0dH water, like on the other Perla apis?