User blog comment:J Fan/QAR Flag in On Stranger Tides/@comment-4967581-20120810161022

That's interesting. I'm guessing that the movie makers just didn't think about what would be Captain Barbossa's Jolly Roger after he had the QAR so they didn't bother to change it.

But I wouldn't be surprised if Barbossa did take his flag because he took eveything else from Blackbeard.