If I remember correctly, I had a bag authenticated by the authenticators here and it was a Made in the United States bag with a L plant code. I'll try to find the post and post it here.
There were at least half a dozen codes that were what I call "Floaters". They were mostly from G to M and were assigned as needed to temporary plants only in use for a few weeks or months, or independent plants where
Coach had simply leased a part of their production facilities. They could and often were used for more than one country so they shouldn't even be given any country designation otherwise someone might think that if that particular code is with a creed that says it's from a different country, someone might think that second bag is fake.
Sometimes a floater code could be used for more than one country in the same MONTH. For instance in 1995 the M code bounced back and forth like a tennis ball between the US and Costa Rica, and in March ("C" month code") the M plant code was used for BOTH plants in the same month. The same thing happened with the M plant code in April of 1997.
To muddy the waters even more, a surprising number of serial numbers in bags from the mid to late 1990s had the 3 digits of the serial prefix scrambled, and sometimes it can take a while to even figure out which is the month code and which is the plant code. One or two people who call themselves "experts" and even "authenticators" STILL haven't figured that out.
Those are just some of the many reasons why I don't make lists of countries and codes. And that's why the only way to be sure they're correct is to compare them with known genuine bags made in the same plant, month and year. Another problem is that some people who don't understand the system just assume that if it has the "right" plant code, it must be genuine, and that definitely is NOT always correct. They look for short cuts, but there aren't any. Or as any hobbit would tell you, "Short cuts make long delays".
Most plant codes will be in bags that show the country of origin right in the creed stamp anyway.