However, I would have expected double pack failure and double engine-failure both to be ahead of cabin VS in the ACARS message hierarchy - they would be in ECAM hierarchy.
Consider this ... let's say both engines are spooling down for whatever reason (supercooled water droplets accumulating in the engine core - read more here ...
http://www.georgehatcher.com/Ice_Cry...To_Engines.pdf) - due to the simple fact that both engines were (potentially) exposed to the same weather effect they might be spooling down one after the other without too much delay. Now I would presume, that the ACARS error message for engine flameout would be triggered below a certain N1 value.
It remains to be calculated what would happen sooner - both engines failing (thereby shedding the AC1 electrical bus and cutting off ACARS) or cabin pressure loss (no clue how much pressure is lost due to imperfect seals and a "normal" outflow valve position) amounting to cabin alt rising those 150 ft that would trigger the CABIN ALT warning.
It would be very helpful if BEA would release the position of both MLGs and both engines in the debris field - might give a good clue if the east-west orientation of the debris field is significant. Why am I so hung up on this? Simply - if the aircraft was heading east-west (or west-east for that matter) at the point of impact, yet as the material analysis shows it hit the water near wing-level it would mean that the pilots were in control of the aircraft. Unfortunately that would open new questions again :/
PS: Apologies for typos ... half asleep :/