The amount of dissolved water present in turbine oils varies (depends on oil viscosity and temperature, where heavier oils absorb/dissolve more water than thinner oils, and more water is absorbed/dissolved at higher temps).
540 ppm of water at the given temp might be OK for ISO 100 oils, but for ISO 46 oil seems grossly excessive to me.
I don’t think that the OEM by recommending maximum allowable conc of 1000 ppm (0.1%) of water suggested that it is safe to operate this oil as long as water conc is under this maximum (e.g. 950 ppm). I would interpret it as the condemning limit (as ReneWA said) that could be reached in a case of incidental water ingression (e.g. cooling coil leak). With regular maintenance of oil (periodic demoisturization and filtration) and without incidental ingression, you are not supposed to have water present in oil nowhere near the recommended max level.