Q.Black Boy Peach trees
I have several Black Boy peach trees all grown from stones. They usually produce a good crop but this season all the trees except for one have very pale/white peaches. I thought it was due to the drought but a friend suggested that they may have reverted. Is this possible also can they cross pollinate? The tree that produced really black Black Boy peaches is on the cold side of my house away from the others.

I have tried with not much success researching your question about your Black Boy Peach Tree.
This peach tree is extremely sought after and seem to be difficult to even purchase!
Black Boy Peaches are self fertile, I don't think cross pollination is the issue.
If you research the colors of Black Boy Peaches, the fruit color varies greatly--some very light, even white to very dark.
If believe you are seeing some environmental changes in the fruit, most likely due to chilling hours.