Malcolm, this is a stunning sunrise captured in a very interesting location. The foreground is interesting and perfectly exposed but I think that the composition fails to focus the viewer on it. If you moved closer to one of the more interesting patterns on the rocks and used a wider angle, you would make that feature more prominent in the frame and create a foreground focal point. I would also consider placing the camera a little higher, this would increase the amount of beach that is visible and help with the mid-ground component of rule of thirds. You have used a custom aspect ratio and I think that it really works well, as does the vertical aspect. Exposure is spot on and you have let just the right amount of sky blow out. I really like the fact that you have left the hills in the background in shadow - this helps balance the image.
Your work has really improved out of sight in the last month or so and this shot really shows that you have the fundamentals down. Concentrate on your composition and very soon you will go from creating good images to great one's!
I don't know, for now I'll let you enjoy the 2AM wakings. I am really wanting to go shoot the sunrise at my work, though. But right now we are in the middle of June gloom. If I get up at 4AM I want at least some chance of sunrise or at least good light for shooting.