Thank you for that link. One of the responders asked this which I think is a good question:
I get why the Federal R&D credit and Federal tips credit, which are general business credits that reduce Federal income tax and reduce the Federal wage deduction, would result in an increased California deduction for wages and no offsetting income to report since California does not conform to those credits and Federal income tax is non-deductible.
ERC is a refundable payroll tax credit. California businesses get to deduct the wages & payroll tax without taking the credit into account, and the refundable credit is tax exempt income?
Clearly a credit that reduces Federal income tax is ignored for CA purposes, because Federal income tax is not deductible.
But a credit that reduces an otherwise allowable deduction, sure seems like it would be taxable to CA.