It is possible to fly to Welcome Pass to start the climb. Otherwise it is a 1.5 to 2 day approach via the Copland Valley. Although it is possible to bivi lower when walking in, Welcome Pass itself is an excellent starting point for summit day.
For approaching from the Copland Valley via the, now standard, Bluewater Route, timing to cross the Tekano Glacier is critical. This is very steep and exposed snow and subject to serious avalanche hazard. Early in morning it will be firm and at awkward angle that will put you on your front points. Facing due north, snow conditions will deteriorate rapidly during the morning.