As far as the random numbers, be careful on the mobile apps.... i've had problems where the numbers change on me when i'm not trying to adjust them, if it's not that, then I don't know
Moisture Balance in your graph is not the same as Allowed Depletion. Imagine Allowed Depletion as how far you want to set that orange bar on your graph, and the moisture balance is just the percentage of where your water level is at between your lowest allowed depletion level (orange) and full field capacity (green). Here's text from Rachio support article
"Flexible Daily Schedules will only water when the moisture level reaches Allowed Depletion (orange line). This is because the system is auto-refilling WITH regard to other irrigation AND precipitation/rain events. The best way to think about Allowed Depletion is like a gas tank. As you know, at 50% your gas tank is half full; but using MAD principals, at 25% it's 3/4 full and at 75% it's 1/4 full. You can adjust the allowed depletion percentage to adjust the watering duration and interval for each zone via the Advanced Settings menu within the zone menu settings.
Everyday we'll look at how much "fuel" your lawn has used and calculate when/if we've hit the refill point (allowed depletion). By default, we set the refill point (allowed depletion) to 50%, however this can be changed to anything from 0-100%; thus the name Management Allowed Depletion, or MAD.
The Moisture Level graphs in the web app will display the percentage of the moisture available within MAD; or how much fuel do you have left before you hit the refill point. As such, if MAD is set to 50% and your Moisture Level graph reads 50%, then your lawn's "gas tank" is really 3/4 full and will be refilled when it's 1/2 full. If your Moisture Level graph reads 0%, then your lawn's "gas tank" is really 1/2 full and ready for a refill. Think of it as a percentage of a percentage. Flexible Daily schedules will always water when the Moisture Balance hits Allowed Depletion.