Nobody has promised that any of you will be released yet.

上句中的yet在牛津词典中

a) used in negative sentences and questions to talk about sth that has not happened but that you expect to happen （用于否定句和疑问句，谈论尚未发生但可能发生的事）

b (used in negative sentences 用于否定句 ) now; as soon as this 现在；即刻；马上

是a)还是b)呢？ 还是都可以？