Given that the service is for the period April 2013 to September 2013, it is preferable to disclose the same only in that period.
However, given that the time limit of 90 days for submitting the revised return (specifically online submission) has elapsed, it will be advisable to prepare a revised return and submit the same to the concerned range superintendent manually (There is no guarentee that he/she shall accept the return, as there is no provision backing up this act in the act).
Please retain the return for your records. Otherwise, there seems to be no other viable alternative, given the present situation.