Notice period changes is email

[CrawlingFromShitshowToAfterglow]

I'm asking on behalf of my niece. We're in the UK. She has worked with a company for 4 years. Her work contract says 4 weeks notice period. But her manager sent an email last year saying all staff's notice period is now 8 weeks. When this email was sent, my niece didn't challenge the change - but she didn't explicitly accept it either. All of the staff just ignored the email.

My niece was offered a new job last week. She handed in her 4 weeks' notice as per her contract. However, her manager has said the notice period is 8 weeks.

How legally binding is an amended email sent by the manager compared to what my niece signed in her original contract?

The company is very small (the manager is the owner) with all HR managed by an external organisation. In order to speak to HR, my niece needs to go through her manager first. There was no email sent by HR about the change of notice period to 8 weeks; it was simply an email by the manager.

Any legal advice would be greatly appreciated before my niece returns to work on Tuesday.

Contractual period of 4 weeks applies .

I'm afraid the previous poster is wrong.

As your daughter has continued working and has not told her employer that she is working under protest or that she does not accept the change, it is likely that the 8 weeks notice period applies. Also, if her contract has a variation clause giving her employer the right to change some terms of the contract including the notice period, the 8 week notice period applies provided her employer has complied with any conditions in that clause.

If your daughter leaves after 4 weeks her employer could, in theory, sue her for any costs they incur as a result of her leaving early, e.g. the additional cost of employing a contractor to cover her role. However, it is unlikely they would do so and unlikely they would succeed. The worst consequence of leaving after 4 weeks is likely to be that she won't get a reference from her current employer, or that any reference will tell a new employer that she left without serving out her full notice period.