@kristinelbly --
"Meaning its possible that CA companies, under MA temporary regulations, could have treated any income earned from 1/1/2021-9/13/2021 as CA based income if that was where the employer worked pre-pandemic."
I think you meant to say that MA companies, under MA temporary regulations, could have treated any income earned from 1/1/2021 to 9/13/2021 as MA based income if that was where the employee worked pre-pandemic.
MA's Covid sourcing rule applied only to MA employers.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
