Return filing deadline shortened for non residents; alternative payment option added and rectification deadline tied to annual return. Amendments to section 39 shorten the return filing deadline for non resident taxable persons, replace the first proviso in sub section (7) to allow filers to pay either the self assessed tax or a prescribed alternative amount, fix an annual deadline for rectification of errors tied to the annual return timetable, and make furnishing details of outward supplies a condition for filing returns while permitting notified exceptions on Council recommendation.