This happened to me today, but it certainly isn't the first time and I wanted to elicit some comments.
On my LHR-ORD flight today, the F/A's started making eveyone prepare for landing a full ten minutes before the Captain announced for them to do it. They were going around in F and pushing everyone's "Reset" buttons on the suite. They also announced for everyone to put their seats up, put eveything away, etc. Then the announcement from the flight deck came.
It certainly isn't the biggest deal in the world, but I (and I'm sure my fellow pax) would have liked to be a little more relaxed for those extra ten minutes. As I stated, this is not the first time this has happend to me (on both domestic and international flights), so I am assuming that other here have experienced it.
Do the F/A's just unilaterally do this becasue they want to get it out of the way early? Are they getting some kind of instructions from the Flight Deck to do it that we are not hearing? If you refuse to do it until you hear the announcement, are you going to be met at the gate for not obeying crew member instructions?