If a taxpayer has already filed a MD return and it has been accepted, they must amend their MD return to get the benefit of the change.
HOWEVER, the Comptroller of MD (tax division) must first set up the rules for how the changes to the tax forms will be implemented and then will they tell the tax software companies how to change their software--both the original returns (502, 505) as well as amended RETURNS (502x, 505x).
When the changes have been implemented please see this TurboTax Help article for assistance in amending your MD return: I need to amend my state return
