9 hours onboard to go nowhere

I'm not referring to a flight returning to origin but one that didn't even leave.

The information from flightstats on British Airways flight BA227 to Atlanta makes for sorry reading. Scheduled departure time from London Heathrow was 2:05pm. My comments are enclosed in [ and ].

At 1:10pm, arrival time updated from 6:31pm to 6:29pm.
[An hour before departure the flight is on time.]

At 1:40pm, departure time updated from 2:05pm to 2:30pm (with corresponding adjustment to arrival time).
[A minor delay, perhaps due to use of a remote stand.]

At 2:35pm, departure time updated from 2:30pm to 2:45 pm.
[Another minor delay.]

At 3:05pm, departure time updated from 2:45pm to 3:00pm.
[The update has occurred a bit late but BA confident delay is not serious.]

At 10:54pm, flight status changed by London Heathrow airport to cancelled.
[Oops. 9 hours after boarding the airport records the cancellation of the flight instead of the airline.]

At 11:10pm, departure time recorded by BA as 6:52pm.
[End of flightstats record.]

The last record clearly is inconsistent with the previous one. Departure time being recorded many hours after the supposed time of departure is suspicious. It indicates the aircraft pushed back but didn't actually depart.

A passenger account on Flyer Talk is consistent with this, and reports that they were onboard for about 9 hours before the flight was cancelled.

Under EU regulation 261/2004 passengers are entitled to care under Article 8, Article 9(1)(a), 9(1)(b), 9(1)(c) and 9(2), and Article 7. Out of hours crew is not a valid exemption to Article 7 under the extraordinary circumstances waiver, but maintenance might be. The other Articles have no such exemptions and so must apply. Article 7 provides 600 euros compensation. Article 8 provides right for passengers to choose between refund of fare or relevant portion of fare (plus flight to return to origin for those who are in the middle of their tickets), or a re-routing under comparable conditions (ie same class of travel) at earliest opportunity. Article 9 requires free meals for the waiting time, hotel accommodation, transfer to and from accommodation, and 2 phone calls/faxes/emails.

Under the new USA passenger bill of rights, passengers would almost certainly have been returned to the terminal around 4:30pm or 6 hours earlier than they actually were.