Post offices across central Arkansas saw a flood of people coming in trying to send their taxes out by midnight on Friday. The I.R.S. estimates almost 40 million people wait until Friday`s deadline to file. They say more than 9 million people will file for extensions. At the Central Post Office in Little Rock, employees were working overtime to make sure everyone`s tax returns got a postmark of April 15th. Most of the post offices were not open until midnight, but they did have workers standing outside with a stamp, ready to postmark any returns that came in before midnight.