User blog comment:CoolJazzman/Ywach, could he be the first Quincy?/@comment-5551986-20130417191601/@comment-6904925-20130422105408

I don't think he was hiding in Hueco Mundo, in 514 it was stated that Vandenreich was in another dimension, in other words a world full of Quinces, but I think that Uryu doesn't know anything about them, his grandfather did in 491 Quilge Opie said to Ichigo during their fight that "Soken rejected the new advanced powers like the Quincy: Vollständig and preferred the outdated Quincy: Letzt Stil", as for Ryuken I wouldn't be surprised if he knows.