Loading for Air Tight PC-1 Supreme

I hv tube phonostage both the Artemis PL-1 and Air Tight Reference ATE-2001. The ATE-2001 has a fixed loading of 47k only.

pardon my ignorance. Does it mean that once a Phono stage utilise a step up transformer, I will have to set the loading based on the internet impedence of the cartridge?

With the PL-1 I seem to be only able to set the impedance based on the loading impedance and not internal impedance. From the leaflet that came with my PC-1 Supreme cartridgem, airtight seems to suggest a loading of 100ohm to 800ohm and preferrably 400ohm. But that leaflet is met for the PC-1 i believe. I wonder if the loading for the PC-1 Supreme is the same as PC-1