Went to bed at 9:15 pm, woke up at about 7:15 am, got about 10 hours of sleep. When waking up i did not feel a difference because i’m usually in bed before 10:00 pm on school days, I did not regret anything because i would have been in bed already by 10:00 pm.
Went to bed 9:30 pm, woke up at 7:00 am got about 9½ hours of sleep. Once again did not feel a difference. Still no regrets.
Went to bed at 9:35 pm, woke up at 7:10 am got about 10 hours and did not fell a single bit different. No regrets at all.