1. The decision of the legislative body concerning a redevelopment area is final and conclusive, and it is thereafter conclusively presumed that the redevelopment area is a blighted area and that all prior proceedings have been properly and regularly taken.
2. This section does not apply in any action questioning the validity of any redevelopment plan, the adoption or approval of that plan, or any of the findings or determinations of the agency or the legislative body in connection with that plan brought pursuant to NRS 279.609.