California watering restriction has been added to firmware 2.1.4. So after upgrading to firmware 2.1.4 you should see this option under Edit Options -> Weather Control -> Weather-based Restrictions.
Getting WaterSense certification is definitely on our todo list, however, we need to first roll out the ET based weather algorithm as it’s required by EPA. I am not sure how much rebate your city gives you. At the moment OpenSprinkler is still priced at almost $100 less than Rachio. So if the rebate is no more than $100, OpenSprinkler is still a good choice without the rebate.