User blog comment:CoolJazzman/Uryu "Last Living Quincy"?/@comment-6904925-20130703091515/@comment-11051098-20130703202935

Ichigo's Quincy powers had not awakened when Yhwach held his Auswählen. He could not possibly have lost his Quincy powers because they were not active.

Maybe Grand Fisher sensed the Shinigami-powers in Ichigo, even if they were not awakened, and attacked him, and Masaki died while protecting her son because Yhwach held his Auswählen and stole her powers just at the wrong time.