http://www.cornsnakes.com/forums/showthread.php?t=129174

I posted. Rich Z agrees, not homozygous caramel. Just as you said... lots of variation and that includes amel. Sometimes, due to the caramel, amels that are het caramel show excessive yellows and oranges. But butters are pretty uniform. Most of the variation is how bright the yellow they are, but they're pretty much all nothing but yellow as they age.