I'd say she is wheaten based. It's certainly possible to have patterns on that background. For example, specked Sussex can be on a wheaten or a brown base and look much the same as adults, the only way they can be definitively told apart is on chick down. Wheaten is yellow and brown is darker and striped.
I find the same in my research, but would seeing as dark brown (Db) can change the chick down to a much lighter color, even on eb and wheaten bases, could the bird be eb/eb - Db/- ? What would that look like? Due to some crosses I've made, I'm fairly confident this particular bird carries at least one colombian-like restricting allele.
How would the stippling pattern appear as evident as it is on an eWh/eWh background?