Kicking the can (down the road)

My flex daily schedule has been misbehaving for some time, and I need to get it figured out.

Yesterday, my Zone 1 showed 8% moisture, and said it would water today. (I have my schedule set to finish before sunrise, so it generally starts around 3AM.) This morning I checked it, and it now shows 0% moisture, and says it will run tomorrow.

We didn’t get any rain, and I didn’t get any notifications, so there’s no explanation from the program as to the reason for the delay.

This has happened several times in the past. What would cause it to procrastinate like this?