Jean Deyol didn’t mind standing in line to mail Christmas gifts to her grandchildren. The Catskill, N.Y., resident said she has spare time during her annual December RV trek with her husband.

Wednesday, they stopped in Vicksburg on their way to Arizona for winter. And, a day after mailing 125 Christmas cards, also getting the packages on their way with time to spare was a relief.

&#8220I always expect to wait. That’s OK. That’s fine,” said Deyol after standing in line with a package for about 15 minutes Wednesday at the U.S. Post Office on Pemberton Boulevard. &#8220Now the packages are gone, and I have an easy heart.”

Deyol is about a week ahead of the panic, according to the U.S. Postal Service, which tags Dec. 21 as its busiest delivery day of the year. In all, the USPS expects to deliver 20 billion letters, packages and cards between Thanksgiving and Christmas. Total volume on the busiest processing day, Dec. 19, is expected to rise to 900 million pieces of mail, up nearly 25 percent from an average day’s load.

Although many companies join the Postal Service in delivery of larger items, USPS expects about 1 million packages to be delivered every day through Christmas Eve.

Wednesday, there were periods of no waiting at the main Vicksburg facility, but other times when the line backed up.

&#8220The 1 1/2 to two weeks before Christmas are usually busier,” said Joey Leist, a clerk. &#8220We’ll be busy throughout next week.”

The deadline for getting first-class mail where it needs to be by Christmas Day through the U.S. Post Office is Saturday, and priority packages need to be in the mail by next Wednesday. Last-minute shipments can go through express mail by Dec. 23.

&#8220We can guarantee service to most places overnight,” with express mail, said Leist. &#8220(Senders) can do it the day before, or two days before.”

United Parcel Service refers to the week two weeks before Christmas as &#8220Peak Week,” its busiest shipping time of the year, said Patti Mathews, owner of the UPS Store a couple of blocks from the post office on Pemberton.

&#8220People come in now and they’re sure their packages are going to get where they’re going on time because they have plenty of time,” said Mathews, who described the December rush as &#8220crazy,” even during rainy days that typically slow business. &#8220Next week we’ll have our ‘Last Minute Larrys.’”

For UPS customers, there is still time to take advantage of the private shipper’s ground service, though the travel time varies: Local deliveries may take only a day or two, but a package en route to Chicago, for example, would take three days, Mathews said, and shipping to the upper Pacific Coast from Mississippi could take a week. UPS also offers three-day select service, second-day and next-day air, Mathews said, but the rates are higher for shipments that take advantage of these last-minute options. Because Christmas falls on a Sunday this year, deliveries need to be en route by Friday.

&#8220You can still send something on the 23rd next-day air,” said Mathews, &#8220but it’s very expensive to send anything Saturday delivery.”

Shipping over the weeks immediately preceding the holiday is up overall, but especially – like most days year-round – during lunch hour. Lines between noon and 1 this time of year can leave brown box-toting post office patrons waiting all the way outside the lobby doors for their packages to be weighed, stamped and filed away to be sent.

&#8220I figured at lunchtime it would be busy,” said Dr. Gordon Sluis, who rested a stack of five boxes on a counter while he waited behind seven other customers on his break from the Vicksburg Clinic Wednesday. &#8220But it was better to take care of it now rather try to squeeze it in the rest of the day.”

Sluis was making his first trip to the post office this Christmas, but it won’t be his last.

&#8220My wife does the shopping… and I do the mailing,” he said.

Despite the wait during rush hours, lines are a bit shorter, in part because most shippers offer Internet sites that allow lables to be printed and fees to be paid. People can also track delivery of their items on several Web sites.