The best German pilot after Marseille

These were not disadvantages...
Regarding 1): the pilot looking into the sun was often blinded by the suns brightness, making the fighter upsun much harder to see.

Regarding 2): True, they are looking into darkness, but that only makes it easier to spot sunlight glinting of the enemy aircraft's wings, canopy, and fuselage.

These were benfits, not disadvatages, which is why all fighter pilots tried to maneuver to attack upsun.

 

The time of day way largely irrelevant, as fighters would maneuver to attack from an upsun position. Still, time of day would require more or led maneuvering depending on position.

But, I doubt a pilot would not attack if he saw the enemy and it was morning, noon, twilight, etc.

 

If the sun is at the pilot's back, he's not looking into the sun. I was thinking more in terms of ground and naval battles, with the former being pertinent here.

The Japanese sank USS Chicago using this tactic. If the cockpit is facing away from the sun, it's not going to reflect much light at all. And most a/c of the era wore camo paint rather than the raw aluminum adopted by 8AF late in the war.

Definitely agree with the last point.