I think some people that are saying it is not the same snake may be making an assumption based on the fact that striped corns hatch striped...they don't get striped because their saddles fade out with time. But apparently yellow rat snakes do undergo a change like that. I goggled and found quite a few pics & descriptions. Here are links to some of the better ones:

Look at the juvie yellow rat snake pictured about half way down the page:
http://www.southalley.com/album_rat.html

Here is an adult:
http://www.scserp.com/SCSPhotoGaller...atSnake001.JPG

So I am inclined to believe it is the same snake. Definitely not a corn though.