Transitional appellate authority mechanism allows existing tribunals to hear GST appeals until the national authority is constituted. The Central Goods and Services Tax Act is amended to provide a transitional mechanism in section 101A. Until the National Appellate Authority is constituted, the Government may, on the Council's recommendations and by notification, empower any existing authority, including a Tribunal, to hear appeals under section 101B. In that event, sub-sections (2) to (13) do not apply, and references to the National Appellate Authority are to be construed as references to the empowered authority.