With regards to announcements, one of the responsibilities for a designated cabin crew position is to make announcements. Now this is not an actual rank, but a number position which cabin crew can work in. It varies according to aircraft type. It bears no resemblence on practising for a leadership role - in fact it could be the most senior crew member or most junior, depending on the position, where they have chosen/been allocated to work.

In terms of the 'cabin crew seats for take off/landing', this is SOP laid down in safety manuals. It is approved by the CAA/EASA and is checked through regular audits by the authorities. As my esteemed colleagues have highlighted, various parts of the aircraft report to the SCCM that cabins and galleys are secured for take off. At this point the SCCM makes the PA and then informs the flight crew that the cabin is ready for take off or landing (again done by various ways dependent on aircraft type). When this is done, as far as flight crew are concerned the cabin/galley is secure and crew are all sat down at their stations. Take off and landing are the phrases used by us at BA, other airlines may differ in their SOP's - but like other safety and procedural formalities, we do things differently to say Easyjet who may do things differently to say Virgin, but all are approved by the regulators.

Kind regards
D1L

These views are my own and do not reflect those of my employer.