Income-tax penalties are subject to a six-month limitation from specified events and require a reasonable opportunity to be heard. Section 472 prescribes a six month limitation from quarter end for passing any order imposing, enhancing, reducing, cancelling or dropping penalties, with the start point tied to specified events (completion of proceedings where no appeal exists; receipt or passing of appellate or revisional orders; or issuance of notice). Penalty orders may be revised to reflect appellate or revisional outcomes but only after providing the assessee a hearing and within the same six month limitation; time for rehearing and periods of court stay (until vacatur is certified) are excluded from the limitation.