Article 149 establishes the timeline for revising assessments. Generally, the Authority cannot rectify or revise an assessment after three years from the date the original assessment was made. This is extended to five years in cases of fraud or deception. For deemed assessments (Article 143 bis), the Authority has a flat five-year period starting from the date the return was originally submitted to make any corrections. These periods balance the state's interest in accurate collection with the taxpayer's need for finality and protection from indefinitely open-ended tax audits.