I'm still waiting to see if my female turns blue, or begins to regain the yellow color. She was a very odd case. When I got her, she wasn't solid yellow, but you could see she was a juvi. She was under 30" in length and grew very quickly over a month time span.
Once added to quarantine, she began to turn banana yellow. After I added her to the reef tank, she started to turn black. I am not sure if it was the lights that provoked the colors, or not.
First day I got her,
July 06 2022
A few days after adding to reef tank. July 22 2022 if I remember right.