That is not a YB.
Interesting normal, but I do not see anything yellowbelly ish to her. Even the belly is not checked like a YB.
If you breed her, breed her to a known morph and invest that time in a guaranteed project.
Hang onto a male that looks like her (or has those markings) and breed him back when the time comes if you want to see if she has anything genetic going on.
Just my 2 cents.
bruce