blackmail or what!!

[formula-one]

My employer has told me that if I do not work the shift (4pm till 2am), he will terminate my employment, what rights do I have, I have worked for them for over 16 years,

[cassa333]

What shift do you normaly do and why have you been asked to change?

[Lil O'lady]

Join a union and talk to your union rep.

[formula-one]

normally work 6-2 and 2-10, the new hours are supposedly beneficial to the company and the employee, the new shifts are 7-3.30 and 4pm till 2am
Iam in a union, the t.g.w.u.and according to my rep, I have no choice but to accept the ultimation

[buildersmate]

So one wonders what different answer you expected to get here.
The employer needs to consult with the employees, or in your case, with the Union (if a collective bargaining arrangement is in place). They have clearly done that, and you've heard the outcome.
The company has to show a reasonable reason for wanting to do this - and I can't guess what that might be. You don't say what line of business you are involved with, but I do find this a bit strange since the purpose of extended shifts butting up to one another is to effect a shift handover. And I don't understand why one shift has to be longer than the other - are you involved in an industry that uses humungous quantities of electricity perhaps, where the price is cheaper at night?

[lambretta12]

If you've been employed over 3 yrs then you have a very good ground.Ask him for what he said to be put in writing.Then go to higher managment & start a Greavance prosidier against him/her that they are verberlly threatening you.Three strikes & they are out!