I bought a gorgeous pale green Regis that had the strap shortened. You couldn't tell from the pictures. The seller gave me a partial refund because she hadn't noticed. I decided to keep it but I have never worn it. The strap is the perfect length to use as a shoulder tote but the bag is really too small to wear that way and the only way you could get away with it as a handbag it to add extra holes in the strap. I am torn as to what to do with it.
You could add extra holes with a leather punch but any time a bag is altered, it reduces the value. The seller should have noticed and noted it in the listing. I own most of the Madisons but a few of them are really quite small.