If I need to amend my 2015 return, and no longer have the 2015 Deluxe CD Program, do I need to purchase another 2015 Deluxe CD Program?

I cannot find the 2015 Deluxe TurboTax program CD that I used in 2015.  But my computer does have a pdf of the 2015 return.  I need to amend the file due to an RMD.  How do I get the 2015 Deluxe program CD?  Is that necessary to do the amendment?