<h1>GST updates: input tax credit mechanisms, refunds, adjudication time limits, e invoicing thresholds, composition and QRMP reliefs.</h1> GST is a destination based tax on supply with a seamless input tax credit system, zero rating for exports, and IGST for inter State supplies; it establishes online registration, returns, e invoicing and reconciliation. Procedural rules cover refunds (60 day disposal, special inverted rate formula, pandemic exclusion from limitation), a sunset clause for adjudication (3/5 years), Advance Ruling with appeal rights, and interest limited to ITC both availed and utilised. Simplified regimes for small taxpayers include Composition Levy and QRMP, rationalised late fees, phased e invoicing thresholds, e Way Bill controls, and reward guidelines for informers.