If the entire amount is repaid within 3 years, the entire amount will end up being nontaxable. Further, if you repay in 3 equal amounts in before the due dates of your 2020, 2021 and 2022 tax returns, no tax will be assessed on this distribution on any of these tax returns. If you instead repay in equal amounts amounts in 2021, 2022 and 2023 after the due dates of your 2020, 2021 and 2022 tax returns, respectively, you'll initially pay taxes on 1/3 of the distribution on your 2020 tax return and, before the 3-year statute of limitations on a claim of refund of taxes paid on your 2020 tax return expires in 2024, you'll need to amend your 2020 tax return and claim a refund of the tax assessed on the 1/3 reported on that tax return.
Before making a CRD, make sure that you actually qualify to receive a CRD, otherwise the normal rollover deadline applies: https://www.irs.gov/newsroom/coronavirus-related-relief-for-retirement-plans-and-iras-questions-and-...
