Lyman;
The term "UAS" was used in the BEA Second Interim Report but not the first. In researching the eight or so AF447 threads the term was used first by Will Fraser on the 23rd of September 2009 and thence by bearfoil on the 24th of December, same year. Whether the BEA adopted the abbreviation or not can't be known. I know some from the BEA have monitored the threads in the past.
The evolution of the UAS drill and QRH checklist is discussed in the BEA Reports. I first saw it around 1998 and it showed up in the FCTM around 2003/05. At that time it was clarified when to apply the memorized items and when to not do the memorized items and go straight to the QRH procedures which prescribed setting pitch and power according to the QRH tables. Typically such circumstances were cruise flight; the memorized items were intended for low-level, during/after-takeoff circumstances where immediate information was required due to the immediate high risk to the flight, (as per Birgenair & Aeroperu accidents). The aircraft is not in immediate danger with a loss of airspeed information in cruise.