You can either have a scheduled program, or switch to Smart Watering.
If you have created a manual schedule and enabled Smart Watering, the manual schedule will continue. Deleting the scheduled run time will allow Smart Watering to create an automatic scheduled runtime. (That is how it worked for me. Also warned that my manual schedule was likely overwatering.)
Water Restrictions allows you to program local regulation of which days and times you are allowed to water.
Smart Watering created the following for me.
First lawn zone has two 18 minute runs
Second lawn zone has three 15 minute runs.
Same grass, slope and shade. Different flow rates and spray patterns.
Little bit of soak time between each run.