Revision of ITR1 for Income added under AY 2014-15 on 09/Aug/2017

I had during AY 2013- 14 commuted my pension (1/3rd) from my previous employer upon resignation. No tax was deducted on the same by the employer. I had filed my returns not stating the the commuted pension as this is not taxable. Today i received a mail from my previous employer stating that the commuted value of pension received from an approved superannuation fund is governed by Provisions of Sec 10(13) of the Act and is taxable if received by employee on resignation (ie prior to retirement). Accordingly my previous employer paid Tax on my behalf and remitted tax to the Govt which is reflected in TRACES for "AY 2014-15" under date of booking "09/Aug/2017" Please advise 1. If i need to submit revised IT return for AY 2014-15 ? 2. Can IT return be revised for AY 2014-15 as one year from the date of Assessment has lapsed ? 3. Ack under Sec 143 (1) received for AY 2014-15. 4. Can i show the pension as Income for the current AY and claim/adjust tax paid as the date of tax booking is on 09/Aug/2017 (but reflected in Traces AY 2014-15)? 5. I need to pay additional tax under Sec 234 B and C if booked under AY 2014-15? how do i avoid the same ? Thanks.