The reason that yellow smiley face is on all the promos is because we’re going back to The Great Game, where we saw Sherlock shoot it. Remember that part of the trailer with an angry Sherlock firing at random inside 221b? And you’ve seen all of the recent promo pics with a destroyed/bombed flat? We know Sherlock is going blind or hallucinating this series, we know Baker Street will be destroyed again – sounds like the blind woman from The Great Game, doesn’t it? The one who heard the soft voice speaking to them?
Keep in mind we never got the last pip. Moriarty counted down from five in The Great Game but never sent the last puzzle. He never handed over the final problem. He imitated it by abducting John and threatening to burn the heart out of Sherlock. But that bomb, like the train car in TEH, was just paused. And series 4 is going to give us that last pip.
