I'm wondering the same thing, especially since it appears the book is already printed (unless Zeboyd has an early proof copy).
On a side note, I broke down and ordered the Enter the Gungeon bundle from Special Reserve. The Ammonomicon book itself is sold out, so the bundle appears to be the only way to get it.
Yeah, I was tempted to try and get in on that Ammonomicon, as I'm a whore for such items, but I had to look the other way and pass. I had to start trimming the fat when and where I can, as some shit I really just don't need(but I guess that could be said about everything really). LOL
Zeboyd stated in that tweet they let LRG take lead on the book and qty's, as they had no clue, but I think maybe 1000 may have been a better bet than just 500.