Proposal to amend UN R51 in the 04 series of amendments based on GRBP-84-07, adding definitions and specifications for Real Driving Additional Sound Emission Provisions applying to vehicles of categories M₁ and N₁, modifying sound measurement methods and test procedures including indoor testing provisions, establishing a sound expectation model for RD-ASEP compliance evaluation, introducing provisions for vehicles equipped with an Automated Driving System, and updating Annexes 3 through 10 and associated appendices with revised test conditions, gear selection flowcharts, temperature and test-track corrections, tyre rolling sound measurement procedures, compressed air noise assessment, and conformity of production checks. No Contracting Party shall refuse to grant type-approvals under the 04 series of amendments from its entry into force until [TBD date], after which approvals under the preceding 03 series may no longer be accepted.