I had some new grass put down and setup a daily flex schedule for every 2 hours. The zones are setup correctly and the schedule is set to begin after 8am. So I’m assuming that it would run 8,10,12, 2pm, 4pm, 6pm. AND it does on the FIRST day only. Why would it start the next day at 12am and run through the night? Totally useless.
Unfortunately, this is the way that hourly schedules work (even @franz recently said that he rues the day that they built hourly schedules). I also would not use daily flex for what you want to do, but fixed schedules.
The easiest way to do what you want is to set up 6 different fixed schedules for the times that you want. I overseed my lawn every year and I have 3 fixed schedules that I use for that (morning, noon-ish, and late afternoon). I leave them in place and each year just change the dates that the schedules need to run.
Once the grass is established, you can change to a daily flex schedule.