Could also be that your "Dawn effect" is kicking in earlier as you're waking earlier. If I leave testing too long after waking up, I know my BGs start to rise even with no food. A half hour delay, like testing after shower, shave etc rather than before, can make a difference of 0.5 to 1.0 in my reading. And it's not co-incidental. I've tested immediately on waking and again half an hour later and seen the climb. So laying in bed not sleeping could do the same maybe?