In summary.....
Many going or gone already to NavCanada including a good few very experienced and highly valued ATCOs.
The rest of us were told last week, almost as directly as this, that the choice is to either go to Scotland - or resign. Simple really and not much opportunity to go south then or now, as those that have tried or are trying to transfer out, will tell you.
There are a few souls around who will go wherever the company sees fit, some begrudgingly - some readily, but not many at all.
So as for how many staff are actually planning for a move up north I'd say not a lot, in truth.