Admission to PRIME and/or JMP only happens after you've been admitted to UCSF. In other words, they won't consider your placement in the PRIME, JMP, or JMP-PRIME programs until after you've been offered admission to UCSF. So, there is no risk to applying for all three... It probably goes without saying, but you better have a good reason for wanting to be in PRIME and/or JMP (e.g., experience with, and commitment to, working in underserved communities for PRIME and/or preferring small, project-based learning of pre-clinical curriculum over traditional lecture format for JMP)
Congrats on the secondary invites, y'all! So happy we get a chance to let UCSF know more about us. There are interview days all the way up through the last week of February! My MS1 friends say a lot of the cool kids in their class were interviewed in February (assuming we get interview invites), so hope springs!