This is an automated computer-generated color scheme, you could say, proving that 4 colors is enough to color a map of countries of any size, shape, location.
(If you mean a human intervention of changing "d" to "c" by itself, for no reason other than because the human could see that "c" will work after the computer figured out everything (wrongly), that's like saying because a program was supposed to give an answer of "32" but it gave "75", just change "75" to "32" and call the program excellent. It does not work that way. We have to figure out why the program gives a wrong answer. Maybe the premise was wrong. In this case, maybe saying 4 colors is enough to color any map was only partially right. Maybe it needs to caution that a country cannot be more than twice long as the rest of the countries on the map for it to work.)
It started out with a unit pattern
A = [a b c d] [c d a b]
and expanded out to all four directions, always following the convention for adding to the front, back, above, below to color more countries without breaking the unit pattern, thus guaranteeing that 4 color solution will always follow. But it does not. As you can see, if you swap "d" with "c" you will have "d d" which follows that the 4 color solution fails. So the conclusion for this scenario of one country larger than the rest is: 4 color solution fails.
c d a d c d a d c d a b a b c b a b c b a b c d c [d d d d d d d d] d* a b a b c b a b c b a b c d c d a d c d a d c d a b becomes -->
c d a d c d a d c d a b a b c b a b c b a b d* d c [d d d d d d d d] c* a b a b c b a b c b a b c d c d a d c d a d c d a b