Delta (DAL) Cancels Hundreds of Holiday Flights on Omicron Woes Posted byZacks Equity Research December 28, 2021 Leave a comment on Delta (DAL) Cancels Hundreds of Holiday Flights on Omicron Woes Delta’s (DAL) Christmas flight cancellations result from the Omicron-induced spike in coronavirus cases and severe winter weather conditions in parts of the United States, among other factors.