When the city council has denied a proposal with prejudice, or when the applicant has withdrawn his proposal after notice of the planning and zoning commission meeting thereon has been made, no reapplication requesting the same zoning classification shall be accepted by the city or scheduled for hearing by the planning and zoning commission within a period of 12 months of the council's denial with prejudice or the applicant's withdrawal. Provided, however, on receipt of a request stating how conditions have changed substantially within the community since the prior denial with prejudice or withdrawal, the planning and zoning commission may waive the mandatory delay period and authorize the acceptance of a new application.