American Airlines passengers are still grappling with an onslaught of flight cancelations continuing through Sunday, making a grand total of over 1,500 flights nixed since Friday. CNN reports that the airline canceled another 634 flights on Sunday—about 12% of its total operations, according to the company. American blames lousy weather conditions and staffing shortages for the schedule changes. “With additional weather throughout the system, our staffing begins to run tight as crew members end up out of their regular flight sequences,” said the company, adding that severe winds in Dallas-Fort Worth, the company’s largest hub and home to headquarters, sharply reduced arrival capacity. Following the pandemic-caused drop in air travel, the sharp uptick of people itching to travel has caused airlines that offered buyouts or early retirement packages to employees to scramble and hire or rehire to keep up with demand.