(b) For exemptions commencing in the first seven years from the date on which the empire zone was designated, the amount of such exemption in any of these years shall be one hundred percent of the "base amount", determined pursuant to subdivision two of this section. In the eighth, ninth and tenth years, the amount of the exemption shall be seventy-five percent, fifty percent, and twenty-five percent, respectively, of such base amount.
(c) For exemptions commencing in the eighth, ninth and tenth years from the date on which the empire zone was designated, the amount of such exemption shall be seventy-five percent, fifty percent and twenty-five percent, respectively, of the "base amount", determined pursuant to subdivision two of this section. 1-a. (a) A municipal corporation may provide in such local law, ordinance or resolution, or in a separate local law, ordinance or resolution adopted after public hearing, that the exemption so authorized shall be for a term of ten years, notwithstanding that the designation of the zone may expire prior to the end of such ten year term. Any such local law, ordinance or resolution shall be applicable only to exemptions commencing on assessment rolls with taxable status dates on or after the effective date of such local law, ordinance or resolution.
(b) Where such local law, ordinance or resolution has been adopted, the amount of such exemption in the first seven years of its term shall be one hundred percent of the "base amount," determined pursuant to subdivision two of this section. The amount of the exemption in the eighth, ninth, and tenth years of its term shall be seventy-five percent, fifty percent and twenty-five percent, respectively, of such base amount. 2. (a) The base amount of the exemption shall be the extent of the increase in assessed value attributable to such construction, alteration, installation or improvement as determined in the initial year for which application for exemption is made pursuant to this section. The base amount shall remain constant for the authorized term of the exemption, subject to the following:
(i) If there is subsequent construction, alteration, installation or improvement during the term of the exemption, the base amount shall be revised to include the increase in assessed value attributable to such construction, alteration, installation or improvement.
(ii) If a change in level of assessment of fifteen percent or more is certified for an assessment roll pursuant to the rules of the commissioner, the base amount shall be adjusted by such change in level of assessment. The exemption on that assessment roll shall thereupon be recomputed, notwithstanding the fact that the assessor receives the certification after the completion, verification and filing of the final assessment roll. In the event the assessor does not have custody of the roll when such certification is received, the assessor shall certify the recomputed exemption to the local officers having custody and control of the roll, and such local officers are hereby directed and authorized to enter the recomputed exemption certified by the assessor on the roll.
(b) No such exemption shall be granted unless, pursuant to article eighteen-B of the general municipal law:
(1) notice of the designation of the empire zone has been filed with the clerk of the assessing unit by the commissioner on or before the applicable taxable status date;
(2) the construction, alteration, installation or improvement commenced on or after the date the empire zone was designated; and
(3) the designation of the empire zone has not ended and has not been terminated by the commissioner on or before the applicable taxable status date.
(c) For purposes of this section the terms construction, alteration, installation and improvement shall not include ordinary maintenance and repairs.
(d) No such exemption shall be granted concurrent with or subsequent to any other real property tax exemption granted to the same improvements to real property, except, where during the period of such previous exemption, payments in lieu of taxes or other payments were made to the local government in an amount that would have been equal to or greater than the amount of real property taxes that would have been paid on such improvements had such property been granted an exemption pursuant to this section. In such case, an exemption shall be granted for a number of years equal to the ten year exemption granted pursuant to this section less the number of years the property would have been previously exempt from real property taxes. 3. Such exemption shall be granted only upon application by the owner of such real property on a form prescribed by the commissioner. The original of such application shall be filed with the assessor of the assessing unit. Such original application shall be filed on or before the appropriate taxable status date of such assessing unit and no later than one year from the date of completion of such construction, alteration, installation or improvement. 4. If the assessor receives the notice described in subparagraph (b) of subdivision two of this section and an application by the owner of the real property, he shall approve the application and such real property shall thereafter be exempt from taxation as herein provided commencing with the assessment roll prepared after the taxable status date referred to in subdivision three of this section. The assessed value of any exemption granted pursuant to this section shall be entered by the assessor on the assessment roll with the taxable property, with the amount of the exemption entered in a separate column. 5. Exemptions existing prior in time to the termination of the designation of an empire zone by the commissioner, or, in the case of a municipal corporation which has adopted a local law, ordinance or resolution pursuant to subdivision one-a of this section, prior in time to the expiration of such designation, shall continue as if the designation of the empire zone had not been terminated, or, if applicable, had not expired; provided, however, that any further increase in the value attributable to construction, alteration, installation or improvement commenced subsequent to the date of termination, or, if applicable, the date of expiration, shall not be eligible for exemption pursuant to this section.