User blog comment:Xilinoc/Ch. 587 - The Headless Star 6 (for real this time)/@comment-5693502-20140702183403/@comment-5693502-20140702190518

I've got an image of Nimaiya pulling out load's of Bankai's from a little brown sack...

But I'm assuming that, barring Kirio, they'd all be familiar with both Yhwach and Yama-jii's bankai due to them being the first Gotei Captains. So they'd have a good idea of what he's capable of. Then again, it works both ways...