Your state of residency for tax purposes is determined by tax law. California's rules for determining residency are complicated, and are detailed in this reference: https://www.ftb.ca.gov/forms/2019/2019-1031-publication.pdf
I suggest you read pages 4-6 to determine if CA is going to consider you a resident (for tax purposes) for all or part of 2020.
Your income - regardless of where earned - is taxable by CA for any period of time for which CA considers you a CA resident.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
