The answer depends on what you are trying to achieve. If you want to reconsider some of the candidates in the earlier requisition, there is no need to "re-open" the previous requisition, as you could simply hire someone from the requisition and note the candidate who backed out as a "declined offer." If you do not want to reconsider the candidates in the previous listing, it is probably in your best interest to re-post the position with a new requisition. If time is of the essence, you can re-open the previous requisition and review new candidates. Your impact ratio analyses will be impacted by the option you select. If you hire someone from the earlier requisition (whether it is re-opened or not), your applicant pool for that position will be the one from which both candidates (the non-starter and the resulting hire) were selected. If, however, you re-post the position with a new requisition (and do not hire anyone from the previous requisition), you can exclude all candidates on the previous requisition, as there was no "successful" hire. Instead, you would only include the candidates on the requisition from which the resulting hire (who does not back out) is selected. Please note that you would only include candidates who meet the definition of an internet candidate in the impact ratio analysis.
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.