Answered by Shaykh Faraz Rabbani
It is sufficient as a punitive expiation for all those fasts. You must still make up all missed or corrupted fasts. Why I am especially inquisitive on this issue is because…
It is clearly stated in Maraqi al-Falah, Ibn Abidin’s Hashiya, and other major Hanafi commentaries and Fatwa collections, that one kaffara is sufficient for all previously missed fasts. There is no doubt about this. This is not an issue of “regional differences,” because Syrians and Indo-Pakistanis use generally the same references.