I was flying from LHR to CPT in Club World (11.5 hour overnight flight) and had done my due diligence on the seats. Upstairs had no availability so I had chosen 20K downstairs as this was a window seat but with direct aisle access (no climbing over anybody). I checked in with the iPhone app when I was able to, and was still assigned to 20K. And when I checked in at LHR and had a boarding pass printed I was still in 20K. But when I went to the Galleries lounge and the agent scanned my boarding pass she told me that my seat "had changed" and I was now somewhere in row 19, which I wasn't happy about as I would no longer have the direct aisle access. I asked her why the change and she did some clicking and then told me that the AV entertainment system wasn't working for that seat so they moved me. I replied that I had no intention of using the AV entertainment system as I would only be reading my Kindle and sleeping and asked her to move me back. Apparently someone else had already been moved into that seat but she was able to switch me back to 20K, after warning me that I should not expect any compensation for the non-working entertainment system. However, when I boarded the plane and settled into 20K the entertainment system was working absolutely perfectly.

The questions this leaves me wondering about are (1) was the claim that the AV entertainment system in 20K was broken an outright lie, given that it was working fine when I boarded? (2) If so, why would they move someone into my seat and then lie to me about the reason? (3) If they were telling the truth, why would someone be moved into a seat with a broken entertainment system? When I was in the boarding line two Club World passengers ahead of me were upgraded to First as they were boarding, so if there was spare space in First Class why would they put someone in a Club World seat with a broken entertainment system?

(BTW at the time my BA status was only Blue which might have some relevance here).