Even though we have very specific watering restrictions (our winter restrictions are one day only, no watering between 9a - 6p on that day), I’ve settled on a Daily Flex schedule. For my plants and trees, the watering has been amazing (summer allows two days per week, so it seemed to water deeply about every 10-14 day, yet water my lawn every day allowed), and before the winter, after 4 years of drought, my yard looked healthier than ever.
I left the Rachio on over the winter, trusting that its intelligence would save me from wasting water. Until today, that had proven correct. Neither my lawn nor my plants/trees zones had watered since October - our crazy winter rainfall has taken care of soaking my yard all by itself. Finally, last week, the increased daytime hours, plus a couple weeks of no rain, gave the Rachio time to water my lawn only. Going to bed last night (my watering day is Sunday, i.e. today), I checked my phone - the sprinklers were set to water not today, but Sunday March 12, and the weather app showed rain in the forecast for 1:45am.
Imagine my surprise to wake up to rain pounding on my roof at 645am (it had been raining since a few hours earlier), then looking at my phone to see the notifications that my lawn cycles had run at 404am. I am seriously upset. I can’t set my sprinklers to water only when I’m awake to cancel if necessary, the long cycles needed for my plants / trees preclude that due to the time of day restrictions. So my ‘smart’ sprinklers were watering in the middle of a rain storm. What happened to the Weather Intelligence? I know our drought is no longer a real emergency, but saving water over the long term was the primary reason I purchased the Rachio.
@chrisandeden, Flex Daily schedules are not recommended for strict watering restrictions. Usually, if you can only water once per week, the Flex Daily will always run on the allowed watering day when temperatures are increasing and rainfall is limited.
I believe you may have confused your lawn and shrub/tree zones. Currently, the zones with the deeper root zones are scheduled to water after the 18th of March 
We apologize for any surprises this morning. The system ran as designed (details below). It’s important to remember that only the zones with the shorter root zone depths (lawn zones) have been running. Additionally, it appears that the root zones for these zones has been reduced from the target/recommended depth of 9 inches to 7 inches.
Let’s review the data available in your moisture graphs:
As of this morning, your zone’s allowed depletion was sitting at 9% Forecasted rain totaled .29 inches…
Looking at next week’s weather, the ET forecast indicates the forecasted rain of .29 inches wouldn’t last until your next allowed watering day (Sunday)…
Taking the current moisture balance as of yesterday (.04) + the forecasted rainfall (.29) and subtracting forecasted daily ET values, your zone’s allowed depletion would have been met on Friday if we didn’t water today.
Some ideas to extend your waterings moving forward include:
- Change the root zone depth to 9 inches for turf zones
- Increase the allowed depletion to 60-70%
- Decrease the crop efficient to 50-55%
For more details on Flex Schedule Fine Tuning, please refer to this support article.
Hope this helps 
You might consider adding a rain sensor to your controller. That would stop watering during or after significant rain, whether or not it was forecast.