If the Wi-Fi connection is lost, for example the router or the internet service is down, the timer will continue to execute the pre-loaded schedules for up to one month. The default setting of Netro Pixie timer's smart watering is level basic and in this level no smart schedule will be generated. If you want to set only smart watering, please go to Settings->Garden->Smart Zone and set level advanced. https://www.netrohome.com/forum/posts/111
Please also note that Pixie is connected to the cloud service through WiFi. Because distanced WiFi connection consumes much power, Pixie will go to sleep mode to save power after 5 minutes when it is manually powered on. Every hour it will wake up to check the latest watering schedules.