We decided that unanswerable questions are allowed. Questions about future events within a series are considered on-topic. These questions should be answered as objectively as possible, but in the end they would be opinion-based until actually information comes along. So where do we draw between these questions and this question for example?
In that One Piece question, OP asked for clarification on Sanji's wanted poster. This information is not known at this point, but will be addressed as the story progresses. I have to admit that at first I too wanted to close this question as opinion-base, but I ended up retracting my vote, because it is still about a future event. So where do we draw the line? When does a question go from being about a future event, to being opinion-based?