This doesn't specifically address the prior year option, but the USUAL rule is if you are are currently married during the year BUT you qualify as Head of Household (you don't live with with your spouse), that your "Earned Income" for purposes of EIC is ONLY YOUR income. It does NOT include any Community Property Income adjustments for your spouse.
Logically, the same applies for the Prior Year Earned Income.
If you are married, but qualify to file as head of household under rules for married taxpayers living apart (see Pub. 501, Dependents, Standard Deduction, and Filing Information), and live in a state that has community property laws, your earned income for the EIC doesn't include any amount earned by your spouse that is treated as belonging to you under community property laws. That amount isn't earned income for the EIC, even though you must include it in your gross income on your income tax return. Your earned income includes the entire amount you earned, even if part of it is treated as belonging to your spouse under your state's community property laws.
https://www.irs.gov/publications/p555#en_US_202001_publink[phone number removed]
