There are two reasons that have brought me to this thought process. Have you ever noticed whenever you give a snake an antibiotic they will go into a shed cycle? Or when they get an infection, like belly rot?
The first time this happened I had a young female, say 200+ grams in a boot box, She either, did not eat or spit up her rat. I noticed it days later when the sides of the tub were brown. I thought she would die for sure because the cage was so bad. After getting everything all cleaned up, she looked fine but I watched her because the smell in the cage could not have been healthy. She went into a shed cycle and then another one right after. When she finished the second shed just a couple weeks after the nasty cage incident a she was white and black. It was the coolest thing I had ever seen. She is all grown up now and produced a clutch of babies this year, with the lesser platty. She looks relatively normal now, and the babies were all normal looking also. But it took 2 years for her to get all the color back.
The second time this happened was last year. I'm not so sure why it happened to this animal but again she shed out white and again she is slowly getting her normal colors back.