Learn about the new GST AATO amendment timeline introduced by the GST Network (GSTN) through Advisory No. 666, issued on July 1, 2026, for the FY 2025-26 Aggregate Annual Turnover (AATO) update. Taxpayers should understand these revised timelines, as they play a vital role in ensuring accurate GST compliance. Under the updated schedule, the AATO amendment window is open from July 1 to July 31, 2026, followed by the tax officer review period from August 1 to August 15, 2026. Previously, under the guidelines issued on May 2, 2022, taxpayers were allowed to amend their AATO details only during the month of May each year. Read more: