This appears to be a UK new site*, and it's definitely not how they usually happen there. In fact, it's not even how they legally happen.

> 100 or more redundancies - the consultation must start at least 45 days before any dismissals take effect

https://www.gov.uk/redundancy-your-rights/consultation

If you want to have similar laws, you need to lobby your representatives, and get them to follow California's example, which introduced the Cal-WARN act:

> “an employer may not order a mass layoff, relocation, or termination at a covered establishment unless, 60 days before the order takes effect, the employer gives written notice of the order”

From https://www.dir.ca.gov/dlse/Cal-WARNAct.html

But as others have said, it's not as strong as the UK laws, so it just becomes a de-facto notice period instead. It's still progress though.

* Although not one I've ever heard of, which is a little suspicious.

There’s a federal WARN act too. Neither the state nor federal versions gives the employees any legal right to try to change the business’s mind.

even in the UK they still get announced as layoffs, employees get their access revoked, and they're in some sort of limbo while the consultations / process takes place.