Well I would assume so, as 3I0 is by definition the Phase to ground fault current. SKM however does some convoluted matrix manipulations to acquire the fault values so it will not be exactly that.
The total fault current will be 3I0, but contributions from individual sources may have the phase current different from 3I0. For instance, the contribution from a grd wye - delta transformer, with the grd wye side connected to the faulted system and no source on the delta side, would have 1I0 in each phase and 3I0 in the neutral.
