Retirement tax questions

It's amazing I found you (or you found me I should say!).  I had a paralegal from my probate attorney's office file for the EIN so she must have indicated a calendar year return (thus the notice assigning the EIN states I must file the 1041 by 4/15/22). Do you know if I have to make a request to the IRS to change it to the estate's fiscal year? Your example of May 15, 2021 to April 30, 2022 happens to be exactly the dates I contemplated based on my mother's date of death. If I'm able to use those dates, I will be able to close out the estate next year without having to wait until 2023 to file the estate's 1041. Thanks so much!