American Airlines is expanding new technology that ensures travelers board with their designated groups ahead of the busy holiday travel season.

The technology, which produces an audible sound if passengers try to board too early, will now be rolled out to more than 100 airports across the United States, according to the airline. American first started testing the technology this fall, the carrier confirmed to Travel + Leisure in October, at Albuquerque International Sunport airport (ABQ), Tucson International Airport (TUS), and Ronald Reagan Washington National Airport (DCA).

“We’ve heard from our customers that the ability to board with their assigned group is important to them because it’s a benefit associated with their AAdvantage status or fare purchase,” Julie Rath, American’s senior vice president of airport operations, reservations and service recovery, said in a statement. “The initial positive response from customers and team members has exceeded our expectations, so we are thrilled to leverage this technology to deliver for them ahead of the Thanksgiving holiday.”

With the new system, travelers who try to board before their designated group will be unable to scan their boarding pass and instead hear an audible sound. The gate agent will then ask the passenger to rejoin the line and wait until their group is called.

Gate agents can override the system for passengers who are traveling with a companion in an earlier boarding group.

American will now roll out the technology to some of the busiest airports in the country, including Hartsfield-Jackson Atlanta International Airport (ATL), and plans to expand it even further in the coming months.

American said the new system also provides insight into how many passengers are in each boarding group, allowing gate agents to better pace the boarding process, and shows the “anticipated arrival time for incoming flight connections.”

The rollout comes ahead of a record-breaking Thanksgiving holiday travel period during which American Airlines alone plans to welcome nearly 8.3 million customers from Nov. 21 to Dec. 3.