(a) Whenever a contract carrier by motor vehicle files with the Arkansas Department of Transportation any schedule stating a charge for a new service or a reduced charge directly, or by means of any rule or practice, for transportation of passengers or property, the department may enter upon a hearing concerning the lawfulness of such charge or such rule or practice upon complaint of interested parties or upon its own initiative at once, and if it so orders, without answer or other formal pleading by the interested party, but upon reasonable notice.
(b) Pending the hearing and the decision thereon, the department from time to time may suspend the operations of the schedule and defer the use of the charge, or the rule or practice for a period of thirty (30) days, by filing such schedules and delivering to the carrier affected thereby a statement in writing of its reasons for the suspension.
(c) If the proceeding has not been concluded and a final order made within the thirty-day period, the department from time to time may extend the period of suspension by order, but not for a longer period in the aggregate than ninety (90) days beyond the time when it would otherwise go into effect.
(d)
(1) After the hearing, whether completed before or after the charge, rule, or practice goes into effect, the department may make such order with reference thereto as would be proper in a proceeding instituted after it had become effective.
(2) If the proceeding has not been concluded and an order made therein within the period of suspension, the proposed change in any rule or practice shall go into effect at the end of such a period.