Tripura GST rules amended: extended timelines, ITC declaration deadlines, gold import credit reversal, UIN and form updates. The amendment extends certain time limits (sixty to ninety days), allows UIN grant after Ministry of External Affairs recommendation, mandates electronic declaration in FORM GST ITC-01 within thirty days to avail input tax credit, prescribes reversal of credit for additional customs duty on imported gold dore bars (one-sixth retained, five-sixths debited at supply), validates FORM GST PMT-06 challans for fifteen days, permits alternative payment routes for specified non-resident suppliers, requires Joint Commissioner-rank members for the Authority for Advance Ruling, and updates registration and TRAN-1 form particulars.