I'm sure that the investigation team will make the decision to ground these types of aircraft IF and WHEN it becomes apparent that there was a mechanical malfunction that could affect the safe flying of other airframes. Note my use of capitals!
No reputable company would jeopordise the safe operation of their aircraft if this could be better effected by the release of pertinant information.
The AAIB have an excellent reputation worldwide, and this is due, in no small part, to the meticulous manner in which EVIDENCE is used to obtain the facts.