(Tax Filing Deadline is Monday)....The deadline is normally April 15.

Not this year. It is because of a Holiday. April 16 is Emancipation Day marking the freeing of slaves in Washington D.C. April 16 this year falls on a Saturday, so it is celebrated ths year on Friday. Because of that, the Tax Deadline is moved to Monday, April 18. That means procrastinators have three extra days to filie their taxes, or to request an extension.