You can take it in any direction you want, but I have pretty low expectations of schools willing to teach my kids from 10 to 16, or mechanics willing to fix my car at 20, or doctors willing to take my blood exam at 22 — all that just because that would be convenient for me.
The modern society started with the Industrial Revolution, when the people understood that there are some very tangible benefits when everyone starts working at the same hour, and started building around that. This building included discarding "local time" (an astronomical fact) in favour of standard time (social contract.)
But not everyone does start working at the same hour. I went to a supermarket today that opens at 07:00 and closes at 23:00, a cafe that opened at 10:00 and closes at 18:00, and a charity shop that opened at 12:00 and closes at 16:00.
When I was working I worked from 08:00 to 16:00 with a half hour break for lunch. But several of my colleagues in the same office worked 07:00 to 15:00. All of us worked with other engineers in countries across the world. My children went to school at 08:30 until 13:30 until they were in senior high school when it was 08:00 to 15:30
The local buses start running at 05:30 and stop at 22:30.
It would be possible to split the day into shifts and have the night owls providing services for other night owls.
Medical emergency cover is 24 hours already. Some factories run 24 hours. So do some transport networks.
There would be huge benefits for commuting because traffic would be spread out.
The practical issues have more to do with noise and energy use, not the "social contract."
And before industrial revolution, people were even more in sync. Whole families/groups slept in one room, so one of you wakes up, everyone wakes up. One insist on staying up, everyone is bothered.
> or doctors willing to take my blood exam at 22
There used to be a system in my country where there were large doctor offices and you didn't really have your doctor, as you had your clinic. (I'm not talking hospital, but doctor's office.)
It was staffed around the day. Each doctor had a work life balance and you could come in whenever. I'm pretty sure this approach works for most service professions.
School can be transitioned to be purely online. Watch video lectures when you want and take online tests regularly. There is really no point to lock all kids up at school for hours each day if the goal is merely to teach them. People leave school illiterate these days, so it's not like it could get any worse.