Your mailing address and your residency for tax purposes are two different things.
Your mailing address is the address you want the IRS or state tax authority to use in case they need to contact you.
Your residency is determined by tax law. As @SundayInSalem pointed out in his original answer, if California was your domicile prior to your going to your parents' home, and your intent was to stay with your parents temporarily and then return to California, then you file as a full-year resident of California.
California's rule is that "Any individual who is a resident of California continues to be a resident when absent from the state for a temporary or transitory purpose".
You will find California's definition of domicile on page 10 of this reference:
2021 Publication 1031 Guidelines for Determining Resident Status
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
