I think that is pushing the envelope a little bit. I have mine start at 3am so the longest schedule I have ends at 7am but I do all my own scheduling. I didn't like how the Rachio calculated things, it's nice to set it and forget it if that's your thing but I like to have more control as it always didn't water when it was suppose to either if rain was forecasted and then we didn't get any(happens a lot).

 

Manual settings is best control. Do not water in the middle of the night. As @Mightyquinn said, even 0300 is pushing it

 

It does seem as though the daily flex schedule will run zones independently, so hopefully rather than running all the zones one night, it will run one or two tonight, another few tomorrow etc. This should help with later start times. I also have it "end by 8 am" which makes the start time even later. One of the default settings is end before sunrise which gives it a start time of around 1:30 am which is crazy. I'm really surprised they allow this on account of fungus concerns. I've read good and bad reviews about the flex daily setup, but I'm willing to give it a shot. One of the things I'll be watching closest is what it does during times of high humidity, when we have hot and dry days like we did this week with high ET I'm less concerned. Although, one thing I just noticed is that the next watering times and days are a full 10 days from today. There is SOME rain in the forecast, but lots of 40% and 20% days. I have a tempest weather flow integrated, so we will see how it all works out with the forecast vs actual rain fall and if it will adjust the next watering cycle.