I'm definitely not a morning person. When I was working shifts at a railway station, I hated the ones which started at 0600. The ones starting later in the day, at around 1400, were the best ones to work overall, simply because I could have a lie-in but still have a shift with plenty to do. However my body clock was actually best-suited to shifts starting at 2200 (although I could get bored stiff doing them).
Now that I'm not regularly working though, I simply get up and go to bed when it suits me. For example, I slept all day yesterday until 10.45pm, and then got up. I've been up since then and I won't be going to bed for a few more hours yet.
So I can end up with sleeping/waking patterns (or, rather, lack of patterns) like the following:
Awake for 30 hours.
Sleep for 14 hours.
Awake for 5 hours.
Sleep for 2 hours.
Awake for 20 hours.
Sleep for 3 hours.
Awake for 4 hours.
Sleep for 15 hours.
Awake for 36 hours.
Sleep for 4 hours.
Awake for 20 hours.
Sleep for 12 hours.
I've never had 'normal' sleep patterns. For example, in my early twenties I only slept for 10 hours per week. (Three hours on Tuesday night. Three hours on Thursday night. 4 hours on Sunday night). These days I need more sleep in total but I can often go for 30 or more hours without any sleep at all. (Things aren't helped by having four active cats either. In the past four years I've never had more than two hours of continuous sleep; it's like permanently living with a young baby!).