It feels like a moving feast with more breaking news to follow shortly (or not).
My guess is that after a cut-off point (which may have already just passed, as the submission form, with the old pricing on it, has now been removed from their site), any new submissions, from existing members or new, will have to be accompanied by the £499 fee (which as I read it is a on-off payment towards future life-time submissions, not an annual fee).
There needs to be clarification, and there is no info (yet) on turnaround times.