You raise several interesting issues here. 1. Preferred qualifications. You can leave them out of job descriptions, and even out of job postings, but they should be documented before they are used to screen out applicants. 2. Job descriptions matching posting. These two should be consistent, but I don't recall there being a requirement that it be so. The issue really comes down to which is the accurate minimum qualification. If you post a minimum qualification that isn't really required for the position, you could be screening out qualified applicants. OFCCP takes the position that if you require a bachelor's degree, it must be needed to fulfill the essential functions of the position; otherwise, leave it out. So, having the requirement in the posting is problematic precisely because the job description doesn't say that it is needed. When determining whether a qualification is a "real" qualification for a given position, OFCCP will consider the people who are currently employed in the position, and the qualifications they have. So, if you are requiring a degree for a position, but you have employees in that position who do not have a degree, you have some potential exposure. The regulations require a regular review of all position descriptions, so take the time to conduct a comprehensive analysis, and then document, document, document.
You can use this OFCCP audit checklist to ensure you're doing what is required to maintain OFCCP's regulations including VEVRAA, Section 503, and EO 11246. Or request a demo to streamline your compliance and recruiting efforts.