What about 3rd shift working?
I work 3rd shift... I'd like f.lux to know that I am a day sleeper... I often sleep from 7am to 12:30PM or later... so when I get up and am online it gets dark way before I go to bed. I was telling it that I lived in Sydney, Australia... since that was about the time I'd go to bed and sleep but now it insists that I live where I do and I can't seem to "trick" it into the sleep/day/night schedule... Not sure how to fix it.
If you're on any of the recent versions, there is a "wake time" setting, and for this schedule we recommend that you set it about halfway through your sleep time.
So if you tell f.lux you wake at 10AM or 11AM it should do about the right thing.