Tax-season procrastinators already have a few extra days this year to get their returns in the mail, but the U.S. Postal Service will still be ready for those who insist on waiting to the very last minute, offering extended hours at select Southland post offices on Tuesday’s deadline.

The deadline for mailing tax returns would normally be Monday, since April 15 falls on Saturday, but Monday is Emancipation Day in the District of Columbia, so the tax deadline has been pushed until Tuesday.

For people who still wait until the last minute, extended hours will be offered at the following USPS centers on Tuesday night:

• The Los Angeles Processing & Distribution Center, 7001 S. Central Ave., with mail collection until midnight

• The Santa Ana Processing & Distribution Center, 3101 W. Sunflower Ave., with mail collection until midnight

• The Santa Clarita Processing & Distribution Center, 28201 Franklin Parkway, with mail collection until 9 p.m.

All post office retail lobbies will adhere to their normal business hours on Tuesday.

WHAT IS EMANCIPATION DAY?

Emancipation Day, an official holiday in Washington, D.C., is usually celebrated on April 16, but is being observed this year on Monday, April 17.

It marks President Abraham Lincoln’s signing on April 16, 1862, of the Compensated Emancipation Act, which freed about 3,100 slaves in the District of Columbia. President Lincoln signed the act nine months before he issued the Emancipation Proclamation. The rest of the country’s slaves were freed by the 13th Amendment to the Constitution, which was ratified in December 1865 after the end of the Civil War.

The Compensated Emancipation Act was funded with $1 million and paid slaveholders up to $300 per freed slave.