Weeping Angels are 'quantum-locked' by observation. However, over great distances, observation doesn't happen instantaneously. If I were to set up with a telescope, light minutes away, could I observe a moving Weeping Angel? A light second? Light years?
Further, if the Angel were moving past me through space at some distant separation, where should I, the observer, look in order to freeze it? Where it was, causing the light to reach my eyes? Where it will be? Is it retroactively frozen, or frozen wherever it is right now?