CUU management cannot sit on the BFS for several more months because negotiations with Teck are not going as well as hoped, IMO.
They can actually probably sit on it for a while and say it's not "done" because they're editing for grammar and spelling. Or because they're using a 3 year trailing price of metals...well everyday that number changes ever so slightly - well you have to update those numbers and now it's not "done".
It's obviously convoluted and out there, but if they're negotiating and don't want it released they can probably say that, and realistically get away with it because we wouldn't actually know when they finished a releasable version. I mean they do only have one shot at releasing it. That said, with there being no leaks (or at least any indication of any) I don't see them as actually having a finished or final copy for very long (if they have one now).
Which begs the question, why such a long wait?