Haha, I've also had a few students who scheduled lessons a little too early! ;) But usually my students are serious and organized.

I used to wonder as well about those wide open schedules some teachers have, but now I sometimes do it myself (well, not 24 hours a day, that's just nuts!) so I understand why.

I travel a lot, and when I change time zones it takes me a while to figure out what my new schedule should be like. So at first, I open it as much as I can (morning to evening), to allow new students to book the times that suit them. After a while, I'm able to design my new daily/weekly schedule based on what works best for both me and my students.

Another detail: as I'm free to make my own schedule, I try to accommodate my students by leaving it as open as possible. However, being available for 8-9 hours a day does NOT mean I intend to teach that many classes! I'm just trying to be flexible. As soon as I have 4 classes booked in a day, I close my schedule for that day, so no one can book any more classes. When I first started teaching online, I sometimes did teach 5-6 classes a day, but that was just exhausting. I know some people do it, but I can't. I'm 100% with my students during my classes, and we have actual conversations (at their pace, and according to their needs and interests), not just grammar drills out of a book, so I need to be 100% present. I enjoy teaching and I want to be the best teacher I can.

I hope this makes sense! :)

Hehe, I find it brave to be available 24 hours, once I had a session with a teacher and I didn't realise it was 4:30 a.m and the session was okay but I could notice the "just-woke-up" face and sometimes you look a bit dizzy and I felt bad for a moment, like " Oh, he could be sleeping more ". 

I can understand it, but it does not always work for students. I once had a lesson with someone who obviously had just woke up and it was early in the morning for them, and they thought I could not understand their accent but I did understand them but it was slurred because it was so obvious they had just woken, for me that does not work because at least if they accept the lesson they should make sure they have got up had a coffee or something and be alert, so because of them thinking I did not understand them I just had to read lists of things and I can read lists of phrases myself or with language partners I do not want to pay someone to do that with! Also he did not really correct me so what did that acheive! I am a beginner but I already knew some of the things I said were not correct!

As a student, I book sessions at strange times and I'm happy when teachers have several time slots available.

I think that nobody really teaches 24h/day. Teachers who have lots of quiet free time and are constantly near a connected computer can easily accept two or three sessions a day at weird hours. I guess they are having naps in between. I also guess that if their teaching day was full, they wouldn't offer 24h days and I don't see why they can't teach once or twice every 8 hours or something.

I try not to assume what other people's morning and night times are. People who work nights sleep in the mornings etc. I can't know if they stay up late or it's their "day time". I'd rather hire someone for a lesson at a time they would otherwise watch TV, than right after their day jobs, when they may be irritable, half-asleep, with one eye on the stove. 

Of course people with 24h schedules should be very disciplined and very responsible with their sessions management and their attendance obligations. 

Thanks for your answers!