Excellent pictures. In the US most breeders don't believe there are any 'pure' IB left. Since your bird is a mutated color it is just as possible he has a little Green blood too. Hybrids don't breed true so anything is possible. There is another possibility that we don't want to see is that he may be a progressive white where they turn white, go blind, and die. Time will tell so enjoy watching him go through the color changes.
Hopefully, it’s not a Progressive White! Can we confirm its color mutation? Could it be Bronze, Midnight, Jade, or something else? I’m very curious to learn what mutation it has.