Have any of you ever observed their Boomslangs chane colors as adults? I got this awesome 6' male Boom

from a person I sold it to a few years back, and when I got him a girlfriend he seemed just fine.

The female had 8 good eggs then died about 3 months later. The male (green) suddenly changed to a jet black color and became viscious (for a boomslang). A year latter now, he seems to be turning back to green.

Boring, yes, but rather odd. Have any of you had this happen with your Boomslangs?
Glad to see ya up and running again.