July 21 (UPI) -- Alaska Airlines announced Monday that its planes were flying again after having grounded them Sunday night due to an unspecified IT problem. "Alaska Airlines has resolved its earlier IT outage and has resumed operations," the company said in a statement . "We sincerely apologize for the inconvenience, and encourage guests to check your flight status before heading to the airport." That statement followed a message posted online around two hours earlier that explained it had