I have central, foveal damage to my left eye as a result of an infection. My early morning symptom is “dark blockage” (central scotoma) on the celing. In the light of day, it is always there, but at differing degree of “darkness”. It permanently obstructs my vision in that eye and has left me with poor functional vision. Mine has no treatment.

Just wondering if yours may be there all the time, but that you are less aware of it in differing light? As someone else said, try the Amsler grid to check.. Good luck!