FYI - IRS provided the below update on March 9, 2021:

Update: Individuals who died in 2020 or 2021 may not have received Economic Impact Payments. If you file a 2020 return for an individual who died in 2020 or 2021, you should complete the Recovery Rebate Credit Worksheet in the Instructions for Form 1040 and Form 1040-SR to determine whether the Recovery Rebate Credit is allowable for the decedent. 

https://www.irs.gov/newsroom/questions-and-answers-about-the-first-economic-impact-payment-topic-a-e...