Before production of the JB series, Jennifer Batten apparently played a Centurion, but now I can't find my notes on this.
However, there's definitely some one-off Battens out there:
Her preference for string dampers is a giveaway.
For some reason, Batten is still listed as a Washburn Signature Artist, though she hasn't had a signature model since 2004.http://www.washburn.com/artists/http://www.washburn.com/artists/feature/Batten.html
Bill Nelson once reviewed a Variax 700, saying he wanted
to enjoy the electronics but this was undercut by the not-so-great work on the guitar part. From the sound of it, Batten hit the same wall. Per an interview published last November --
I took a little hiatus from Washburn for a couple of years because I was so excited about the Line 6 Variax, but I'm back with Washburn and I've conned them into putting the electronics of the Variax into a new Washburn Parallaxe electric and I was hoping to take it out on this tour, but I've stumped them with the electronics.http://www.musicradar.com/news/guitars/one-for-the-road-jennifer-batten-630253
They're going to have a big release in October, right when the tour is over. So what I'm taking out is my old Washburn that I've been using for 15 or 16 years; it's not available any more, it's called the JB100.
The only guitar she mentions on her website is indeed the Parallaxe, with a link to the Washburn site.