legal notice for shift changes

[gingerflaps]

hi, ive just recently found out by a freind that my work place is changing the shift rotas from 8hrs to 12 hrs. I havnt been at work for 6 weeks due to an accident at work. My freind at work says that our shift patterns with change at the beggining of september, but i've had no word from the h/r department or managment that we will be going on 12 hr shifts at the beggining of september. I know there is a certain amonut of time the company has to give you by law before they change your contract, but not sure how long, i thought it might be 3 months..does anyone know the legal amount of time needed to be given?

[padders]

Legally, the company only have to give you 7 days notice of a change of roster