No, 440 line-to-line gives 254.3V line-to-neutral which for most PSU's is above their max Vin rating of 240v.
Line-to-neutral V=440/1.73
As for amps for each phase-to-neutral, It is still only a maximum of 100A per leg but yes, 300A total is possible but only if the loads on all phases are in balance to minimize neutral currents.
ref
https://en.wikipedia.org/wiki/Three-phase_electric_powerThe calculation is right, if you divide 440 by root 3 you get exactly 254.03V , but i doubt he reads 440v exactly, so there is a good chance he ends up somewhere around 240v, i am not very familiar with the standards in the U.S tho i know the rest of the world uses 380/220v 3/1 phase.
but all that aside, even at 254v he would still be able to run S9s with no problem using APW7 psu from bitmain which has a range of 100v to 264V.