nwilliams August 1, 2019 How long are T4A slips available on ACORN? T4A slips for the current calendar year (January to December 2009) will be available on the Student Web Service/ROSI on February 21, 2010, and T4A slips for future calendar years will be posted on SWS/ROSI on February 21st every year thereafter. Students can view and print forms as needed for information purposes only. Paper copies are mailed to students for the purposes of filing income taxes. Students who require PIN reactivation can view instructions for PIN reactivation. By February 2016, T4As for the most recent seven years will be available on SWS/ROSI.