Please do go to a briefing and make up your own mind, rather than be swayed by conjecture, teabreak gossip and NO rants on here.
The same question was asked at ours. My understanding is the the vote is a union ballot for member of the pension scheme who are in the union. The result of that ballot will be presented by the union to the NATS board as an indication of the feelings of the employees.
The NATS board can take note of the resulting ballot, but their legal duty is to the company and shareholders and as such to them the most important thing is to keep the company running and viable. The legal requirement for a consultation stage is going on at the moment. Once that is over (end Dec?) then the board will decide what to do. A No vote does not stop NATS going ahead anyway, or removing the deal put down and coming back with a worse one (or a better one, but I ain't chancing it).
What the union do in the result of a No vote, they said they don't know. Read into that what you like.
Just a point for the union official haters out there and to balance opinion (cos its all a little one sided!) - the union representatives left our briefing with a round of applause and thanks from many of the employees for working hard to minimise the impact of this. Think about that before you jump on the NO bandwagon. The majority of views on this PPRUNE thread are not necessarily that of reality.
RS