hmm, sounds like my EBB is toast, thanks to EMS for sorting me out.
On a supplementary note, I’ve been interested in using pens with the WCB, and I’ve had success with the Platinum Souhitsu Fude Pen CFS-250 (http://www.cultpens.com/acatalog/Platinum-Souhitsu-Fude-Pen-CFS-250.html), most brush pens are quite thick to fit in the holder, but this one is perfect.