I don't know if this has been raised or not. I was on a United flight from (EDIT - I am taking this out) yesterday. The FA's were talking in the front about the incident. One of them told the other that the reason the reason they boarded the passengers first and then needed to remove four was because someone didn't notify the GA.
Basically they boarded the aircraft and two pilots and two FA's showed up afterwards, they had the right authorization but the FA would have had to look in "the notes" to find them and not on the list (I am trying my best to interpret company lingo into plain English).
So the GA then had boarded a full flight and now these four walk up. Neither the GA or the 4 employees were aware there was an issue until far too late. The problem was the due to the way the 4 employees were entered into the system. Whoever did it only entered it on a placeholder and not the actual manifest.
The GA then calls __________ (insert company term, I took it to mean headquarters or ground operations or logistics group) and is told these 4 employees do need to get onboard.
The GA is now stuck in the worst spot imaginable because its up to her to get people off. She goes on board and asks for volunteers. (engines start winding up so I'm hearing less of the story) The supervisor gets on and mistakenly thought they only had authorization up to $800, when in fact she had wiggle room.
We all see the video and what happens next.