I confess to a degree of surprise at no Special Bulletin from AAIB a week on. As with Sumburgh, and in view of the similarly high profile nature of the type/role, I did expect an early indicator to give reassurance (assuming reassurance is in order). The statement 'both engines delivering power at time of impact' re Sumburgh did much to dispel rumours about fuel starvation or MGB/other major component failure being the root cause (whilst still leaving proper space for the detailed report to find in due course on root/contributory causes and aggravatng conditions).
Other posters have referred to the 'process of elimination' in investigation, and some insight from the AAIB into what can be/has been positively eliminated so far would be useful.
The current complete vacuum is creating some pretty unhelpful 'heat without light'