FAIRFIELD-SUISUN, CALIFORNIA Delta Air Lines has established warehouses and cooler facilities in Atlanta, Detroit, Los Angeles, New York and Seattle to store the vaccines. (Luis Sinco/Los Angeles Times/TNS) Vaccines are finally here. But could they affect holiday shipping? The U.S. Postal Service doesn’t normally deliver on Sundays. But if you’ve seen your regular mail person zipping through the neighborhood on the weekend lately, it’s not a dream. As logistics and delivery companies try to avert a holiday “shipageddon” amid the pandemic-inducted e-commerce boom, logistics companies expect to clock thousands of hours of overtime and hired tens of thousands of new full-time and seasonal workers this year.