Santa's little helpers can't always be on time.
FedEx Corp. admitted on Thursday that it couldn't make all of its scheduled deliveries by Christmas Eve, due to inclement weather, record shipping numbers and last-minute holiday surge shopping.
But on Friday, a representative with FedEx told The Huffington Post that some heroic workers are sticking it out for Christmas Day shifts.
"FedEx Express employees volunteered to work Christmas Day shifts for the benefit of our customers," the representative said in an email. "FedEx Express continues to run limited delivery operations in some markets to deliver shipments that could not be delivered before Christmas due to unforeseen volume and severe weather in some areas of the country."
The rep couldn't say how many packages weren't delivered in time.
The company anticipated moving a record-breaking 317 million parcels between Black Friday and Christmas Eve, a 12.4 increase in year-over-year volume.
Still, FedEx hasn't quite been able to satisfy every customer, if social media is any indication:
The counters at the company's Express offices were open Friday from 9 a.m. to 1 p.m. FedEx's other offices were closed.
Household deliveries are given top priority on Christmas.
Customers can find out if their delayed shipment is scheduled for Dec. 25 delivery or available for pickup by checking fedex.com or calling 1-800-463-3339.
The Associated Press contributed to this report.