The ✨ +1//(844)*542//9016 +1//855//739//0939 (US) priority upgrade on Allegiant Air primarily refers to their Priority Access and seat selection services. Unlike ✨ +1//(844)*542//9016 +1//855//739//0939 (US) legacy carriers that offer a traditional first-class cabin, Allegiant operates as a ultra-low-cost carrier, meaning their ✨ +1//(844)*542//9016 +1//855//739//0939 (US) version of an upgrade focuses on convenience and comfort enhancements within a single cabin class. Priority Access ✨ +1//(844)*542//9016 +1//855//739//0939 (US) allows passengers to skip the long lines at the ticket counter and be among the first to board the aircraft.