Sec. 21.4. (a) The appraisals of the parcels in a group under a county's reassessment plan prepared under section 4.2 of this chapter that are subject to taxation must be completed as follows:
(1) The appraisal of one-third (1/3) of the parcels shall be completed before August 1 of the year in which the group's reassessment under the county reassessment plan begins.
(2) The appraisal of two-thirds (2/3) of the parcels shall be completed before November 1 of the year in which the group's reassessment under the county reassessment plan begins.
(3) The appraisal of all the parcels shall be completed before January 1 of the year following the year in which the group's reassessment under the county reassessment plan begins.
(b) If a county assessor employs a professional appraiser or a professional appraisal firm to make real property appraisals of a group of parcels under a county's reassessment plan, the professional appraiser or appraisal firm must file appraisal reports with the county assessor by the dates set forth in subsection (a).