1310A says

"Who Must File If you are claiming a refund on behalf of a deceased taxpayer, you must file Form 1310A unless either of the following applies: 

• You are a surviving spouse filing an original or amended joint return with the decedent, or 

• You are a personal representative (defined on this page) filing an original Form 40, Form 40A, or Form 40NR for the decedent and a court certificate showing your appointment is attached to the return. 

Personal Representative For purposes of this form, a personal representative is the executor or administrator of the decedent’s estate, as appointed or certified by the court. A copy of the decedent’s will cannot be accepted as evidence that you are the personal representative."

You could complete a 1310A and attach as a PDF if it is required. https://revenue.alabama.gov/wp-content/uploads/2017/05/1310A9-16.pdf