From #CNN:

"Passengers who board before their assigned group will trigger technology that makes a sound to alert the gate agent."

Comment: So what happens when the team member asks the passenger to wait for their turn and the passenger (e.g. a #MAGA) refuses? What if they blow right past the team member and head down the runway?

https://www.cnn.com/2024/11/20/travel/american-airlines-line-cutting-boarding/index.html