Projects in Progress. The provisions of this Ordinance shall
not apply to any construction project for which a valid zoning permit
has been issued prior to the enactment of this Ordinance, with the
provision, however, that construction, has substantially commenced
as defined in this Ordinance, within six months after the issuance
of the permit and with the further provision, however, that in the
case of permits granted in the Shoreland-Floodplain District that
substantial construction is completed, as defined in this Ordinance,
within 15 months after the issuance of the permit.