Thanks for the insight. I didn't realize that much hi could disappear as a fish aged. I know they can change their patterns, but didn't think that much. I have one that started as a chagoi and is now so dark it might as well be a magoi. Got another that started as a very faint ki matsuba is now turning to a faint hi matsuba. But completely losing all hi, that's impressive.
Talking about shiro utsuri, I actually sold a gin rin butterfly today. It was an absolutely GORGEOUS fish! Still is, just not at our store. lol