Emperor Angel Question

[-Chewy-]

Hi all,

I have a question on the emperor angel, Pomacanthus imperator, how long does it take for the color to fully change from juvenile to adult

-Chewy-

 

[Navarre]

Years!
I know an Emperor Angel that is 4 years old (well 4 years in the tank so i dont know the true age) and its just beginning to show some discolouration to its bold stripes.