I've seen people taking exams every week and finishing ALL of their theory exams in like 2 months. This is a very rare thing and I'm not even sure that those students passed the CPNE or NCLEX. How fast you go depends on your level of motivation, your study habits, and how hectic your life is.
Something to keep in mind: No matter how fast you complete your exams, you WILL wait 3-6 months to take your CPNE PLUS 6-8 weeks for graduation to process PLUS how ever long it takes for you to get at NCLEX testing date in your state.
Something else to keep in mind: Most RN bridge programs have at least a year wait time. You can be finished or almost finished with your Ec degree before you would even make it off the wait list of most brick and mortar schools
Finally, if you are looking for a "quick and easy" way to get your RN, it doesn't exist
. Ec is a lot of work and very challenging, maybe even more challenging than brick and mortar schools.
EDIT: I also forgot to add that it WILL take you at least two months to take the FCCA, regardless of how fast you completed other courses as it is not work-at-your-own-pace as the other exams are.