At Eat’n Park headquarters in Homestead, the Smiley Cookie production line gets started at 3 a.m. This time of year, a good chunk of the restaurant chain’s signature item will be shipped as gifts, some as far away as Alaska and Hawaii, spokeswoman Daphne Brown said.

“We expect to ship about 3,500 packages this year. Last year, it was about 2,800,” Ms. Brown said. Christmas and Valentine’s Day are the busiest holidays for shipments, she added.

Retailers rely heavily on shippers around the holidays to get gifts to customers on time.

Many are wary of entrusting too many packages until the last minute, after shipping problems last year saw many deliveries delayed until after Dec. 25.

The U.S. Postal Service, FedEx and UPS have all bulked up their holiday shipping operations, expecting shipping volume to top last year’s figures.

But what can retailers do to ensure they’re not overpromising on what shippers can actually deliver?

“The e-commerce shipping model isn’t sustainable in its current form,” said Yossi Sheffi, a professor of engineering systems and director of the Center for Transportation & Logistics at the Massachusetts Institute of Technology.

“You cannot build a shipping network to operate 365 days a year based on a spike in packages three days before Christmas.”

At Strip District-based Pennsylvania Macaroni, Rose McNeil said she’s especially careful this time of year not to promise something will be delivered by a certain date.

“If I deliver it myself, I can guarantee it,” Ms. McNeil said. “But I tell people, ‘Don’t wait until the last minute.’ FedEx isn’t Santa.”

Since PennMac ships a lot of perishable items, including cheeses and meats, there’s a three-day turnaround for most of its deliveries, Ms. McNeil explained. “A lot of our gift boxes are pre-made, but we still have to plan to have enough, because they’re too time-consuming to make on demand.”

Ninety percent of PennMac’s holiday shipments are headed outside of Pennsylvania, Ms. McNeil said.

But, according to the National Retail Federation, procrastination is still the name of the game for shoppers.

“Many consumers are going to wait and see how great the promotions will be later this season before making any commitments,” the group’s president and CEO, Matthew Shay, said in a statement.

“Retailers have reacted to this ‘wait and see’ mentality with fewer October deals and a much quieter entry into November, when we’ll start to see retailers ramp up with offers for exclusive merchandise, deep discounts and unique online savings opportunities.”

FedEx reported that last year it handled 275 million shipments between Thanksgiving and Christmas, and it expects volume this year to rise to 290 million shipments, an 8 percent uptick.

It expects its peak day to fall Dec. 15. FedEx’s Ground division is based in Moon.

UPS is anticipating some 585 million holiday packages, which would be an 11 percent bump from 2013. The company said it expects its busiest day to be Dec. 22.

Ms. McNeil said since Christmas is on a Thursday this year, it makes trying to do last-minute deliveries even more challenging, especially if a customer wants perishables.

“I tell everyone, order early,” she said. “You can’t wait until that last week.”

Kim Lyons: klyons@post-gazette.com or 412-263-1241. Twitter: @SocialKimly. Reuters contributed.

First Published: November 20, 2014, 5:00 a.m.