I have, on a couple of occasions, had DC's walk up to me and tell me that I am dreaming, when I've had absolutely no idea about what was going to happen. I think it really goes to show that your subconscious mind has a lot more of an idea of what's going on, and can really help you out if you let it

I do think that you could have something like a DC tell you that you're going to become lucid sometime soon. If your DCs are telling you, it likely means it's coming straight from your subconscious somewhere - and it knows what it's doing!