12.1. As from the official date of entry into force of the 01 series of amendments, no Contracting Party applying this Regulation shall refuse to grant or refuse to accept type approvals under this Regulation as amended by the 01 series of amendments.12.2. As from 6 July 2022, for vehicle types of category N1 without twin wheels fitted on an axle, Contracting Parties applying this Regulation shall not be obliged to accept type approvals to the preceding series of amendments, first issued after 6 July 2022.12.3. Until 6 July 2022, for vehicle types of category M1 up to a maximum mass of 3,500 kg and without twin wheels fitted on an axle and until 6 July 2024 for vehicle types of category N1 without twin wheels fitted on an axle, Contracting Parties applying this Regulation shall accept type approvals to the preceding series of amendments, first issued before 6 July 2022.12.4. As from 6 July 2022, for vehicle types of category M1 up to a maximum mass of 3,500 kg and without twin wheels fitted on an axle and as from 6 July 2024 for vehicle types of category N1 without twin wheels fitted on an axle, Contracting Parties applying this Regulation shall not be obliged to accept type approvals issued to the preceding series of amendments to this Regulation.