Hello,
I have this same question. I have been buying an updated cartridge every year (a group of my friends has an All-32 team tournament every year on a trip we take in October), but my past sources to buy one have dried up or don't appear to have updated anything yet, and I haven't been able to find any other such listing for one...
I need this badly, so I can defend my 3x back-to-back-to-back champion status, hah! It was won with the Cleveland Browns last year, because Myles Garrett was the cheat code (think Lawrence Taylor from the original).
-LR