You know, I actually didn't even notice most of them the first time through.
Though in fairness, I read it
fast. Like, super fast. And actually, the original panels are still there. You can right click, do "Open in new tab" and then in the address, remove the word "retcon", and it links to the original image.
And I heard about the caucasian thing, though secondhand. It's my understanding that he removed it because people took it as conclusive proof that the kids were white, instead of a-racial, like he's said before. Actually, I think I have the tumblr post were he talked about it. I may go look for that later.
Also, the mayor died? As in, actual death? I mean, I've read through where John comes in and changes things, and then his future self stops him, is that the part you're talking about?