@syseng68k
Sorry, but I just don't believe in such coincidences
Something doesn't add up. Okay, the AAIB have concerns surrounding the evidence they seen about the actual ignition source. I suspect the Li batteries in the ELT may or may not be to blame. Forensic examination of the battery housing should establish relatively quickly whether an external heat source was involved. Likewise if the heat generated by a battery short radiated beyond the casing etc..
Methinks the AAIB is taking a very cautious approach.