Being late in a dream usually reflects self-imposed pressure -- the sense that time is slipping away from an opportunity that matters, whether or not the stakes are actually as high as the dream makes them feel. It often shows up during periods when you're worried about falling behind in waking life.
The rising of the Sun and the indiscrete glances interrupt the spirituality of the nocturnal celestial bodies. - Picatrix (Andalusia, ~1000.AD)