Filing for DACA Holder

Hi everyone I have a question that will hopefully get some response. I am a U.S. citizen and have been living with my boyfriend for five years. We plan to get married soon. He is a DACA recipient, and I would like to petition for him.

In 2023 and 2024, I had strong income. In 2024, I also petitioned another family member. My 2025 income is lower, but after withdrawing money from my 401(k), my total income is about $37,000, which is slightly above the poverty guidelines.

My main question is about the Affidavit of Support:

If my soon-to-be husband already has 40 Social Security credits (which I understand is now included with the I-485 Adjustment of Status), would I file Form I-864W instead?

Or would I need to file Form I-864A (Contract Between Household Member) since we live together and can combine our income?

I would appreciate any clarification on which form applies in this situation.

PS: We don't file tax jointly since we are not married yet.