Did you continue to work for your California employer after your move to NY? If you did, and if your work after the move was entirely done remotely from NY, then your income after the move is not taxable by CA. It is taxable only by NY. In that situation you would not have income taxed by both states, and you would not be entitled to an "other state credit".
CA taxes non-residents only on CA-source income. Income earned from work actually (physically) performed within New York is NY-source income, regardless of the employer's location.
W-2 income is "sourced" where the work is actually performed.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
