(a) An appeal under this subchapter, Subchapter D, or Subchapter E is de novo and based on the test year presented to the municipality.
(b) The commission shall enter a final order establishing the rates the commission determines the municipality should have set in the ordinance to which the appeal applies.
(c) In a proceeding involving the rates of a municipally owned utility, the commission must enter a final order on or before the 185th day after the date the appeal is perfected or the utility files a rate application as prescribed by Section 33.104.
(d) In a proceeding in which a rate change is concurrently sought from the commission under the commission's original jurisdiction, the commission must enter a final order on or before the later of the 120th day after the date the appeal is perfected or the date final action must be taken in the proceeding filed with the commission.
(e) In a proceeding not governed by Subsection (c) or (d), the commission must enter a final order on or before the 185th day after the date the appeal is perfected.
(f) If the commission fails to enter a final order before the expiration of the applicable period prescribed by Subsections (c)-(e), the rates proposed by the utility are considered to be approved by the commission and take effect on the expiration of that period.