With regrard to Managers and Unions, times have changed since I left Hotpoint but here is how it worked for me:

The shop floor at Hotpoint was "closed shop" and when I joined the company as a materials handler (labourer) for the production department, I had to join a union and like the majority became an AEU member (there were a handfull of Transport and General members).

When I became a staff member (thier term), I joined part of the company that was not closed shop. I had to resign from the AEU (I can't remember the exact reasoning but I think it had something to do with a staff member and a shop floor member being on different sides of disciplinary procedures) and was given the choice of either joining a "management" union or donating a comparable sum from my wages to charity. I like most of the other staff members who weren't qualified engineers joined ASTMS which later merged with other unions to form MSF.

MSF does represent Managers but I am not sure what the heads of departments such as mine,the Production Control Manager, or the Works manager did. I don't think that they belonged to any union.

Jon