If any UK staff are affected, then I would talk to citizens' advice (or a solicitor if you can afford it) asap.
Know your rights: https://www.gov.uk/redundancy-your-rights/consultation
You’re entitled to a consultation with your employer if you’re being made redundant. This involves speaking to them about:
why you’re being made redundant
any alternatives to redundancy
If your employer is making up to 19 redundancies, there are no rules about how they should carry out the consultation. If they’re making 20 or more redundancies at the same time, the collective redundancy rules apply.