yellow belly pastel

so i have an 08' pastel, got him at the hamburg reptile show, i was looking at his belly today and i noticed he kinda looks like a yellow belly compared to the pics online, not a strong yellow, but its clear with some pattern on his sides that is consistent with YB pastels, what would be the tell tale sign that he could be a YB pastel ? also what are the chances ? is that a recessive trait ? his parents were both pastels... thanks ahead of time for any help/insight

Your best bet is to post some pictures.

YB is not a recessive trait, so for your snake to carry it, one of the parents had to be YB. I guess it is possible that one of the parents was a YB pastel and the breeder just didn't know it, but it seems unlikely.

YB generally considered a co-dom trait. It is also called "het for ivory" because the "super" form is an ivory.