And if you joint changes color are you going to redo it again. There was probably NOTHING wrong with the joint regardless of its color.
I have never seen one change color, I have asked around and no one else has seen one go white either.
I tried to take a cell phone pix of the joint, but it is really crap with a close up detail picture. There looks to be a bunch of small cracks in those joints that can not be seen in any other joints. That was the motivation to cut it out.
I have attached a picture of a good joint. They are a nice bright yellow. I did not realize the fusing cement was a different color in the USA.
My neighbor is a master plumber, with the big trade union here. He does new installs only on high rises and large condo projects. I hate asking advice because every time the poor guy goes outside to cut the grass or shovel snow, someone is asking him for advice. I sucked it up and asked him about it, he had 2 things to say:
1) Don't use ABS anymore, use PVC
2) More than likely the joint was moved or manipulated before the cure process was finished.
Tonight I glued a scrap joint together, just to see.
I tried to pull it 2/3 apart and then re position it, after it was in place for only a little bit. Sure enough, the soup of the pipe fusing together was white. I will assume my neighbor is right and the pipe was twisted during the curing process.