Originally Posted by
Speed of Sound
Also, only certain aircraft are being inspected which makes me think that they have very quickly established a commonality among the affected airframes which could be a single production batch, a single production location or a single supply of raw materials.
That seems far more likely than the so far unsubstantiated rumour that the cracks affect only aircraft retrofitted with the SS winglets.
If the latter had been true, the association would have been made by now and we would all know about it.