1041 for 2020 filed late (9/2021). Money disbursed in 2021 along with K-1. Do beneficiaries amend 2020 tax return for the K-1 received in 2021?

Person passed 9/2019. Estate elected calendar year so return for 2020 was due 4/15/2021. There is taxable income for the beneficiaries on the K-1. The 1041 filed 9/2021 was both initial and final return.