Further, if 447 was lost at 0214+, that would time the messages at ~four minutes, and its prelude possibly ~4 minutes. If, as above, the a/c was on published route, perhaps until 0206, when attitude and turbulence induced handling qualities diminished, the time span of accident behaviour would be ~8 minutes, an average ROD of 4,500fpm. Consistent with BEA, its speed at impact would be somewhat higher.
The four minute reporting frame supports a flight path without large heading and altitude excursions (no "spin", no "disintegration"). Not without its challenges, this mode may have then deteriorated (rather than recovered as in Q and NW), to produce the flight aspects at entry suggested by BEA.
Will