Depends on a lot of factors.
When are they offering the first CE CBT exam? January or April?
If it's April, and you think you're close then you should register for the first possible exam. Take a short break for the holidays, start studying hard with the supplied PDF reference in early January and kicks its ass the day it comes out in April.
If it's January then you may want to wait a few months. Unless you've been studying hard with the PDF reference since early-November and your recent score feels like a near-pass then you may not be ready for the exam come early January.
Regardless, future examinees should be very familiar and comfortable with the PDF reference(s) before they go into the CBT exam.
I know I personally wouldn't be ready to make the sudden shift from books to PDFs. Even for work I still use my old worn and trusted books to look things up, despite that it may be faster to use google or an electronic source.