I'm afraid that it always has to be borne in mind that the booking does not belong to the passenger in such circumstances. Someone else has made the arrangements and not all of the details of these arrangements may have been disclosed to the passenger by the organiser. The airline certainly shouldn't disclose them for the DP reasons referred to above.

Who knows, perhaps the organiser has made a special arrangement to take the whole of the upper deck for the group? Individual passengers then moving themselves into F could ruin a group event, and a poor soul who's not part of the party could suddenly find themselves allocated into the middle of it.

If a passenger finds him or herself frustrated by the implications of this then their ire should, IMHO, be directed at the organiser, not at the airline - whichever airline it may be.

Indeed, if an agent or booker was instructed to make group arrangements, and then individuals sought to deviate from them, the agent/booker would probably get significant grief from the client as well as potentially creating a lot of work trying to work out where passengers had 'gone'.