Those days are gone. I went to a party last night and I was both home and in bed before two, and I am so incredibly groggy now.
Partly, my ability to sleep in is not what it once was. Also, my regular sleep schedule is very different now from what it used to be - it's easy to sleep till eleven when you never have to be at work before two in the afternoon. But also, my body is maybe more aware of its limits. Or I'm listening more. Or maybe the limits are a bit smaller than they were. Not quite sure.