The imposition of the tax set forth in § 19-1102 with respect to the value of property on the dates set forth in § 19-1103 shall be effective if and when a court of competent jurisdiction should declare, in a final order from which no further appeal is allowed or with respect to which the time for appeal therefrom has expired, that the tax authorized by the Act of June 17, 1913, P.L. 507, No. 335, as amended, is unconstitutional. Should such a court order be issued, no payment or return shall be due under § 19-1102 until ninety days following the date on which such order becomes final and not subject to further appeal, notwithstanding any due dates to the contrary in § 19-1103. To the extent any such court order invalidates the tax authorized by the Act of June 17, 1913, P.L. 507, No. 335, as amended, only with respect to certain classes of personal property, the tax set forth in § 19-1102 shall only be imposed, and the credit set forth in § 19-1103(1)(b) shall only be calculated, on such classes of personal property.