Thanks for the AD link.
Personaly I don't see a direct link to this thread.
It appears that Boeing simply issued a modification to an existing service bulletin and the CAA in an abundance of caution in their current fishbowl raised this to an AD.
No where does it cite new information based on formal investigative findings.
BTW
Hotdog
The judges have decided that it is premature to award you a gold medal for the best theory about what caused this incident
