Furnishing details of outward supplies: electronic return submission and recipient acceptance windows govern amendment and rectification obligations. Every registered person, except specified exclusions, must electronically furnish details of outward supplies for each tax period by the tenth day of the succeeding month and communicate them to recipients; furnishing is disallowed between the eleventh and fifteenth day, though the Commissioner may notify extensions. Recipients must accept or reject communicated details between the fifteenth and seventeenth day, amending the supplier's return. Unmatched details may be rectified and tax and interest paid in the relevant return, but no rectification is allowed after the September return or the annual return, whichever is earlier.