I don't have a specific answer to your question, but I know that our school, it is common for students to skip (with permission of the instructor) Spanish 5. So there is some ability to skip years when appropriate.
Also, according to the MCPS website, "The prerequisite for all courses, except 1 A, is either successful completion of the preceding course or a local placement test."
(
https://www.montgomeryschoolsmd.org/curriculum/languages/)
Placement tests surely vary across schools, and this is typically used for new student placement, but it opens the door for a conversation with the Spanish instructor.
(In MCPS, so many things vary across schools that this is probably always the answer-- contact your school/Spanish teacher for a conversation.)