A look inside the nation's busiest U.S. Postal Service canceling facility during the holiday season

PONTIAC, MI-- The busy season inside the largest United State Post Office canceling facility in the nation is just beginning.

According Karin Nowatzke, Lead Senior Manager Distribution Operations of Michigan Metroplex, the facility has the largest volume of cancellations of any processing facility in the nation, handling aproximately 62 million pieces this December alone.

A cancelation is "the process to make a live postage stamp unusable, usually at the point of original entry into the mailstream. This is done by using a facer-canceler machine or a handstamp and is one of the first steps in mail processing."

The Michigan Metroplex processes all First-Class cards, letter and flat mail collected in the entire Southeast Michigan area.

The 900,000 square-foot facility operates 24 hours a day, 7 days a week.

Since Nov. 23 the Michigan Metroplex has already processed over 17.6 million pieces of mail.

The Pontiac facility has handled over 1 million pieces of mail than the next highest processing and delivery center in the nation, which is located in Texas.

The U.S. Postal Service expects Dec. 14 to be the busiest mailing day of the holiday season and Monday, Dec. 21, to be the busiest delivery day.

"Now is the time to get those holiday cards, letters, and packages in the mail," said Detroit District Manager Lee Thompson.

The postal service will be delivering delivering packages earlier in the morning, later in the evening and on Sunday to accommodate.

Nowatzke warns senders to be careful of their envelope and pen choice when addressing letters.

Nowatzke held up a red envelope with shiny silver writing on the address line that the computer can not read and had to be hand processed. Always use black ink when addressing the letter she advised.

According to the USPS it, "expects to deliver more than 15.5 billion cards, letters, flats, and packages during the 2015 holiday season. In addition, it is projecting that approximately 600 million packages will be delivered between Thanksgiving and New Year's Eve -- an increase of 10.5 percent over last year's volume."

Check the USPS mail-by-dates to make sure your card or package gets their in time this holiday season:.

Mail-by Dates (Domestic Services):* Dec. 15 - Standard Post: Ground service for less-than-urgent deliveries and oversized packages.

* Dec. 19 - First Class Mail: Service for standard-sized, single-piece envelopes and small packages weighing up to 13 ounces with delivery in 3 business days or less.

* Dec. 21 - Priority Mail: Domestic service in 1, 2, or 3 business days based on where your package starts and where it's being sent, variety of Flat Rate options.

* Dec. 23 - Priority Mail Express: Fastest domestic service, guaranteed overnight scheduled delivery to most locations. Some restrictions and exceptions apply. Please note, Priority Mail Express postage refund eligibility is adjusted for shipments mailed Dec. 22 through Dec. 25.

Visit the USPS website for more information on mailing and shipping during the holiday season.

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