; (B) whether exemptions, waivers, or other allowances that permit additional on-duty time or driving time have a deleterious effect on the physical condition of drivers; and (C) whether differences in the manner in which drivers are compensated result in different levels of burden for drivers in complying with hours of service rules. (c) Publication Not later than 18 months after the date that the Secretary initiates the comprehensive review under subsection (b)(1), the Secretary shall publish the findings of such review in the Federal Register and provide for a period for public comment. (d) Report to Congress Not later than 30 days after the conclusion of the public comment period under subsection (c), the Secretary shall submit to the Committee on Commerce, Science, and Transportation and the Committee on Environment and Public Works of the Senate and the Committee on Transportation and Infrastructure of the House of Representatives and make publicly available on a website of the Department of Transportation a report containing the information and analyses required under subsection (b). (e) Revision of guidance Notwithstanding subsection (a), the Secretary shall revise the Department of Transportation guidance published on June 7, 2018, titled Hours of Service of Drivers of Commercial Motor Vehicles: Regulatory Guidance Concerning the Use of a Commercial Motor Vehicle for Personal Conveyance (83 Fed. Reg. 26377) to establish specific mileage or time limits, or both, for the use of personal conveyance. (f) Definitions In this section: (1) Motor carrier; motor private carrier The terms motor carrier and motor private carrier have the meanings given such terms in section 31501 of title 49, United States Code. (2) On-duty time; driving time