Ohio Rev. Code § 4907.27
After schedules are filed as provided in sections 4907.25 and 4907.26 of the Revised Code, no change shall be made in any schedule, including a schedule of joint rates, or in any classification, except upon thirty days' notice to the public utilities commission. All such changes shall be plainly indicated upon existing schedules, or by filing new schedules thirty days prior to the time they are to take effect. The commission may, for good cause shown, allow changes upon less than the notice specified in this section, or modify the requirements of this section in respect to publishing, posting, and filing of tariffs, either in particular instances or by a general order applicable to special or peculiar circumstances or conditions. Copies of all new schedules shall be filed as provided in section 4907.26 of the Revised Code in every depot, station, and office of such railroad thirty days prior to the time they are to take effect, unless the commission prescribes a less time.
When a change is made in an existing schedule, including schedules of joint rates, the railroad shall post a notice in a conspicuous place in every depot, station, and office, stating that changes have been made in the schedules on file, specifying the class or commodity affected, and stating the date when such changes will take effect.
R.C. § 4907.27