There clearly is a link.
My DR is greatly influenced by sleep/time of day in the following ways:
1. If I don't sleep enough (8 hours) multiple nights in a row, all of my symptoms worsen and I even get new ones like perceptual distortion and brain fog.
2. I start the day with an initial phase of bad DR, weird proprioception/difficulty coordinating movement very precisely. In about half an hour things get better for a few hours. In the morning I am usually at my peak cognitive abilities. Everything I have gets significantly worse as the day goes by, though. In the evening, at about 8pm I'm fucking worthless, I can't even understand what I read without making an effort. The magnitude of this effect depends on how much I exert myself that day.
3. I have strange hypnagogic states, but not unusual hypnopompia. I have hypnagogic hallucinations. Sometimes I dream while only half asleep. Hypnagogia was precipitated by the same event (taking atomoxetine) that started my DR.
