"But why not waive Cap 599E if test negative? This one I'm not sure."
"If you test negative for COVID-19, you probably were not infected at the time your specimen was collected. However, that does not mean you will not get sick. It is possible that you were very early in your infection at the time of your specimen collection and that you could test positive later."
https://www.cdc.gov/coronavirus/2019...g/testing.html
After a few weeks quarantining and testing thousands of people, the CHP should have a lot of data about where the risk lies. If it turns out, say, that of those testing negative, none develops symptoms after something like a week, then there'd be practical grounds for reducing the quarantine period.