I emailed the Comptroller of Maryland on February 15, 2021 regarding this question. The reply came that you must send an amended return and that they will have the forms on their website "soon."
I am waiting for the TurboTax software to update with this change. I just finished my taxes after updating TurboTax today and it shows the unemployment income as taxable still.
I am hoping that TurboTax will get with the program soon.
