Discharging taxes

[B49R]

My wife and I are filing chapter 7. Our attorney told us that we can discharge our personal income taxes owed if they are over 3 years due. In 2001, our accountant had to file an extension and did not get our taxes done until Oct. 15th (we signed on Sept. 30th). Will we be able to use the April 15th deadline still and file after April 15th of this year to discharge these taxes from 2001, or will we have to wait until the date we signed our forms or the date the accountant filed them for the 3 years to have passed to discharge these? Thanks!