User blog comment:Godisme/Everything But The Rain/@comment-4822693-20130227224040/@comment-1489595-20130302224238

Where was it confirmed that either Asguiaro or Luders were Quincy in life?

I don't doubt that the souls of dead Quincy can become Hollows after death. But the wiki only mentions Arrancar under race which isn't unusual since the Vadenreich are actively recruiting arrancar. Nor does it state that the two were previously Quincy in life.