There’s a major upgrade coming for United Airlines and JetBlue passengers, and we’re not just talking free checked bags. The two travel giants are teaming up for a new alliance called Blue Sky that’s set to change the game for airline passengers.

The airline says the change with domestic flights will increase efficiency and streamline their process. The added time will help their agents assist those who make the cut with their luggage, seating and arrangements. Starting on June 3, the airline will start enforcing this rule, without exceptions.

U.S. travelers flying with United Airlines will have to check in to domestic flights a little earlier starting next week. That