There is no time limit for completing the coursework and graduating. The course does progress from start to finish, one course unit at a time but there is no time limit for each unit. The units are sequential so there is no skipping around but you can take as long as you want. Your access to the material will not end. The only exception is the final exam which is a timed unit.
There are about 82 course units and each may take on average 1 hour if studied and comprehended. In addition there are many hours of videos in the resource section.
Depending on your current knowledge, it may take a veterinarian or trained equine dentist a week or two while someone learning this for the first time may need a month to complete the studies.
You will need to add 5 days (plus travel) for the hands on training in Florida.