If you work for the post office, you're a civil servant. The Civil Rights movement focused on the notion that all American citizens were entitled to the same basic civil liberties.
There is also time limit to consider for sending the amended returns, and it is generally three years from the time you filed the returns or two years after the tax payment (whichever is later). If you plan to amend more than one tax return, you have to file separate 1040X for every one you want to change.
This statute is a big tricky. You have three years from the date of the original deadline of the tax return to claim your refund or two years from the date the tax was actually paid, whichever is later. For example, your 2016 tax return is due on April 18, 2017. If you add three years to this filing deadline, you have until April 18, 2020 to file your 2016 tax return and still get a tax refund. If you wait any later than that, your refund expires..