When this marking is on a pure monochrome colonist (white, black, or non-tinted silver) then this marking can be from one of the other base coat ranges for that species, including cream or charred. On multiple-tone markings, this rule applies to either one or both of the markings but if it is applied to both, it should be from the same base coat!
Note: The marking should still follow its lighter value/darker value rules.