How do you tell a Jumbo from a non Jumbo?
Jumbos are deeper, have a HUGE lower bout and have curved corners on the upper bout.
Dreads have squared shoulders on the upper bout and the lower bout is not as large, nor are they as deep.
Washburn has produced some "southern jumbos", which IMHO are very much like the "Advanced Jumbo" that Gibson/Epiphone produce. The AJ500RC I have fits comfortably into an Epiphone Masterbilt Dread case, so depth and overall body dimensions are closer to a dread than to a jumbo. The "Advanced" part apparently refers to the bracing under the top, which is reported to be much closer to the soundhole, or "advanced" from the more rearward position of the ones to which it is compared.
I think the wood in the guitar you posted must be maple....although bubinga does come in some stunning quilted patterns, so that could be bubinga, too.
I hope the eBayer posts here on your thread, but I wouldn't hold my breath...
Cheers from Dugly