[swombat]

I think what matters most in that respect is probably whether you get enough sleep, rather than when you get that sleep.

I slept at very normal times, but nowhere near enough, while launching my first start-up on the side of a full time job, and that definitely took its toll.

[johnnybgoode]

True, how much matters a lot more than when. But is sleeping for 8 hours a day at unusual times worse than sleeping 8 hours a day at normal times?

[MaysonL]

After you've done it long enough, there are no unusual times to sleep. Most months I will sleep at least once for each of the 24 hours.