There’s a bright spot in UPS’s recent delivery nightmare: its own employees using social media.

As a result of a combination of factors, UPS didn’t get packages to thousands of customers by Christmas. Bad weather, an improving economy and a surge in online spending nobody predicted—which also kept people out of malls—led to more packages than UPS’s system could handle. FedEx had the same problem but UPS bore the brunt of the bad publicity. In addition to media coverage, unhappy customers took to Facebook and Twitter, among other channels, to let UPS know just how badly the company had ruined their holiday.

It wasn’t just gifts sitting in warehouses instead of under trees. One customer said it was Christmas dinner, ordered weeks in advance but shipped at premium one-day pricing to ensure freshness. Another customer said it was her son’s prescription medication that was caught up in the holiday jam. On Twitter, one local TV station solicited interviews with locals whose packages didn’t show up.

But customers and media weren’t the only ones expressing themselves in these conversations, particularly on the UPS Facebook page. The company’s social media team was engaged, thought not terribly effectively. Posting a whimsical graphic wishing customers a Merry Christmas “from Sana’s helpers in brown” led unsurprisingly to derisive feedback. There was no UPS post about the missed deliveries, either.

Yet front-line employees—empowered by a clearly communicated social media policy inspired in part by IMB’s—took to Facebook to defend their employer.

Driver Larry Ledet was one of the employees standing up for UPS:

His comment generated 917 likes and 145 replies. While most shared their missed delivery stories, few made it personal with Ledet and many expressed appreciation for their work. UPS’s social media team responded to many of the comments, but they also took a minute to thank Ledet for his service to the company.

They did the same for Samantha Vance, a 14-year company veteran, who pointed to the number of packages ordered only two or three days before Christmas, then said “The people in brown give up their families the month of December and unusually the weather gave us a challenge. I would just like to say Merry Christmas to all the UPSers out there!!!!! Enjoy your holiday and your families today.” (I’ve cleaned up Samantha’s spelling and punctuation.)

That comment generated 641 likes and 115 comments. Again, there were a lot of complaints in the comments, but they were all civil—they were, after all, talking to Samantha, not a company logo on a Facebook page. And there were those, like Jim Lynch, who admitted to being one of those last-minute shoppers, then said, ” Thanks UPS and the UPS drivers for doing everything you can for me!! I recognize the challenge, and appreciate the effort!!”

Even though the company has a lot of work to do to repair the damage from Christmas and ensure there is no repeat next year, leadership has to be satisfied with a social media policy that led employee ambassadors—including drivers, who are generally union members—to have the company’s back.