Deductions & credits

I have filed an extension, and the return is extended to 10/15/21. But as I stated, I will not receive the K-1s until early September, past the Additional Payment Determination Date. If I file my return after that date (as would be the case if I wait for the K-1s), the Economic Impact Payment (EIP) would then be based on 2021 AGI, not 2020 AGI. My 2021 AGI will be above the threshold for an EIP. That is my dilemma,