This is correct, unless you have restrictions. The system will determine if it needs to top off the bucket to make it to the next allowable watering day. This functionality has been the same since flex software release last year.
I wanted to make sure the flex system was working correctly in your instance, and noted you do have it set to only water on even days. In that case, sometimes flex might want to top of your zone buckets. I looked up your zone run and that’s indeed what it did. Flex knew it would bottom out tomorrow (which is an odd day), so it topped off your zones today 
Here is some metadata regarding the zone run I retrieved from our audit logs.
Watering 0.02 in. because we will need to water on 2016-05-23 based on the forecast and the next possible watering date is 2016-05-24.
