Hi Max, I haven't seen anything conclusive on root cause, although if you were confident enough to say you expect it to happen again but the problem is benign you should have an excellent understanding of what's going on.
One would certainly hope so as the probability of occurrance is amply demonstrated.
An interesting question for the AME's would be of all the occurrances, has it always been on the same foot location re. a/craft orientation ? i.e. is this a one out of four location issue only, or is it happening randomly ?