Can I re prelim a project once I have been notified that a Notice of Completion has been filed?

The 20-day prelim can be served anytime during the project, but, it only reaches back in time 20-days. So, for example, if you forget to serve the 20-day prelim and 40 days after you commenced your work you then served it. In that case, the first 20 days of your material, labor, services, etc., should not be included in any lien you may record at a later date, but all your material, labor, services, etc., within 20-days of service of the 20-day prelim., and all your work, labor, materials, services done thereafter, is captured and may be included in any lien you may record at a later date. So, in your case, serve it if it captures some of the material delivered within 20 days prior to service ofthe prelim. That said, if a NOC has been recorded you must record your lien within 30 days of recodation of the NOC. I suggest you talk to a construction lawyer asap. I hope that helps.