My experience is it's not uncommon. I'm still printing negatives from 10 years ago, but they are usually negatives that I have not yet printed. Is that new work or old? (In this regard I've known painters who have worked and reworked paintings over decades. They consider it created when they're done with it.) I guess when one considers the way our culture equates NEW with IMPROVED, it shouldn't come as a surprise.
Best, Doug Schwab