User blog comment:Xilinoc/Ch. 597 - Winded by the Shadow/@comment-24384892-20140918224717/@comment-11051098-20140920111513

We can only see the side of the head and hair of the Sternritter who confronted Ukitake. If you look at Nianzol, his hair seems to be long only in the back, except that it looks about the same shorter length. He could have been wearing a cloak in the first invasion, and if you add the high collar, he could be the mysterious Sternritter confronting Ukitake.