Hi there and sorry for the very late reply. Basically haven't logged in here since I got the job with EK
As to the evacuation procedures:
1) due to the nature of crew complement and passenger profile only English commands are mandatory. Use of a national language is optional depending on situation, however not recommended, not to confuse other crew members
2) an evacuation can only be initiated my cabin crew in "catastrophic" situation. I.e. Ditching, broken fuselage, fire, imminent smoke thread
As per cabin crew training the main objective states."To whatever situation a trained procedure is not applicable/ can not be used, use common sense and communicate action with senior crew members/ flight deck"