I recall having this discussion a year ago, and daydreaming about walking past everyone in line at the Apple store in the morning with my new 4S. (Not that they would know it wasn't a 4.) It didn't happen. I did end up at the store with my 4S later that day, but by then the line was gone and they had still not sold out.
I searched and did find a bunch of people posting that they got the 4 early two years ago, plus someone I talked to personally said he did when the VZW came out, but I could not find anyone getting the 4S early last year. If anybody posted such here on the forums, or elsewhere, please post the link here so we can settle this. So far as I can tell, though, it may have been true for iPhone 4 but not 4S.