But please do not call it "Challenging" the boards, you have to have completed the required amount of hours in order to be able to sit for the exam. You are stiing for it, the same as any other nurse that completed the appropriate amount of hours in an approved nursing school
The only ones that can truly "challenge" the PN exam, are those that were corpsmen in the military, and that can be done only in California and Virginia. And licenses obtained that way are noever endorseable to another state.
But be aware that each state has its own requirements on this, as well as the curriculum in your school must be acceptable to CA BRN after you complete the junior year of school.
You may also want to check out some of the mentoring programs in the hospitals in your area, they are available only to RN students, and not if you had your LVN. Especially if you want to go to some of the specialty areas. Salaries for LVNs are not much different from the nurse tech positions and you may find yourself losing out on some excellent opportunities. Also there are very few LVN positions available in hospitals in CA anymore.
Please do some further checking before signing on the dotted line and see what will be available to you with the LVN and what will be available to you as a student.