So i have seen baby lucys and they are a dirty grey around the head does that go away as the grow up?
If the snakes has this shading as a baby it will also have it as an adult. Mojo BELs & Mojos crossed with other het for BEL morphs will have shading on the head- this can be grayish to lavender in hue & opaque to opalescent in saturation. Especially nice is the Hypo-Mojo-Lesser as the effect is subtle & wow at the same time. I personally do not care for the solid white Blue Eyed Lucys, but if you do the Lesser X Lesser or Lesser X Butter does produce them.
I'm pretty sure only super mojaves have the gray heads. Mojo crosses have a stripe, but are overall white from what I've seen. The lesser and butter leucistics are solid white.