Notice needed to change contract of employment

[Kilco43]

Sister just been asked to drop one day a week starting on 1st April. She has been working for company for 27 years in senior position. Had a brief meeting with a manager and no consultation - can that be right?

I was told that to change terms of contract they need to give a weeks notice for every year worked, but hopefully someone can come along and clarify in case things have changed.
You say they have asked your sister to do this, has she agreed to it? If she has then that’s different, if she hasn’t already agreed she can go back and ask for the full notice period before it starts.

It depends. Out of the blue with no consultation or rationale it’s just a pay cut and that would be a breach of contract. If it’s part of a wider program to reduce costs to avoid redundancies and other people agree, it might be reasonable