So they knew it would collapse due to the fact that it was, what, on fire and in danger of imminently collapsing, and had that text prepared, but the anchor mistakenly read that text instead of the text saying "___ tower will collapse at any moment."
There's nothing strange about that at all. It's like when obituaries for famous people accidentally get published before the person dies - they have these things ready in advance so they can announce it ASAP when it happens.
And BBC is a UK channel, not American (British Broadcasting Corporation).