We experienced an regrettable experience exactly where we had to depart the plane immediately after boarding, Soon before the scheduled takeoff time, and re-board. The rationale given was that a passenger felt ill and needed to cancel their programs and therefor their luggage had to be observed and removed. See https://flightstobaltimorefromlondon.blogspot.com/2024/12/book-tickets-of-first-class-flights-to.html