1. Telecommunications companies may file proposed tariffs for any competitive or transitionally competitive telecommunications service, which includes and specifically describes a range, or band, setting forth a maximum and minimum rate within which range a change in rates or charges for such telecommunications service could be made without prior notice or prior commission approval.

2. The commission may approve such a proposed tariff for a transitionally competitive service only if a noncompetitive or transitionally competitive telecommunications company demonstrates, and the commission finds, that any and all rates or charges within the band or range are consistent with the public interest and the provisions and purposes of this chapter. To the extent any proposed band or range encompasses rates or charges which are not consistent with the public interest and the provisions and purposes of this chapter, the commission shall have the power, upon notice and after hearing, to modify the level, scope or limits of such band or range, as necessary, to ensure that rates or charges resulting therefrom are consistent with the public interest and the provisions and purposes of this chapter.

3. The provisions of sections 392.220, 392.230, and 392.500 shall not apply to any rate increase or decrease within the band or range authorized pursuant to this section. A telecommunications company shall file written notice of the rate change and its effective date with the commission within ten days after the effective date of any increase or decrease authorized pursuant to this section.

4. Any tariffs that have been approved by the commission prior to September 28, 1987, which establish a range or band of rates within which range or band of rates a change in rates or charges for such telecommunications service could be made without prior notice or prior commission approval shall be deemed approved by the commission. The provisions of sections 392.220, 392.230, and 392.500 shall not apply to any rate increase or decrease within such band or range.