We've had a lot of problems getting folks to follow through and actually take the written exams.
I administered one a couple months ago where the examinees list slowly whittled itself all the way down from 14 a few months before to 3 on exam day.
That exam set had to be combined with another set the same way yours did.
Part of the problem is the length of time we have to schedule ahead of time.
Folks think they will be available for study and to take the exam, but things happen, work gets in the way, etc, and before you know it, nearly everyone who said they were going to take the exam reports back saying they can't take it.
Another problem is that you need "critical mass" to hold an exam prep class. Its a big commitment to attend as well as to teach. The number of written-qualified examinees is far smaller than the pool of folks who want to take it for the first time, so even in my region (Seattle area) where there is a relatively high number of qualified people, folks still don't go to the classes because its simply too far to drive to get there on time week after week.