Without looking too deep into your schedules it is probably due to this.
There are a couple workarounds that people have used to get around the issue. We have not had time to dedicate engineering to this issue.
Also, as a new user trying out flex daily I typically recommend starting with one or two zones (front/back?), dialing them in, making sure it is watering appropriately, then rolling out to other zones.
Please let us know if you have additional questions.
