And why do you suppose that they're unable to record the wake events? They don't need metadata from Signal: they can make their own, which is precisely what I've been trying to say this entire time. That's enough for them to reconstruct your social graph.

Signal is seemingly built around providing the image of anonymity and security, but has glaring design flaws which negate these.

I'm sorry, I seem to have given the impression that I doubt your ability to play six-degrees-of-Google-breaking-Signal. I do not doubt that. You've ably demonstrated your ability.