Clarification with a caveat: I am not one hundred percent sure of this rule, so feel free to let me know if you see something in the books to contradict this, but you do not have user access, you are still going for Security access.
It isn't a tiered format, each level of access is it's own full test and failing to reach a higher level does not mean you can 'settle' for a lower level that your rolls would have reached.
BTW, just finished finals week, so if my response has seemed spotty, that is the reason.