United Airlines is about to once again confront Unite Here, the labour union that has for months been seeking to get United’s 2,700 in-house food catering workers into the Unite Here fold. Unite Here organisers say they and some of United’s catering workers will be present Tuesday outside Terminal 7 at Houston George Bush International, where United has a major hub. Tuesday, United plans to unveil the fourth of what eventually will be a network of exclusive Polaris lounges for travellers in the carrier’s Polaris international business class cabin. Unite Here organisers and United catering workers previously set up a high-profile picket line in front of Chicago’s Willis Tower last month while United was holding at that location its annual meeting presided over by CE Oscar Munoz. <br/>