Ref:
https://www.newham.gov.uk/Pages/Service ... onies.aspx
It says:
When you receive your invitation letter from the Home Office you will need to phone us on 020 8430 2000 ext 71106 to book your ceremony. You must have your ceremony within three months of receiving your invitation letter.
We can usually arrange for you to join a group ceremony within a few weeks. Ceremonies are usually held on Tuesdays at Newham Town Hall. We do not conduct ceremonies on Saturdays.
If you wish to arrange a ceremony quickly or you would like to celebrate becoming a British citizen in a more personal way, you can book a private ceremony. Private ceremonies are held at Newham Register Office throughout the week. You will have to pay a fee for this service.
Citizenship Ceremonies
Newham Register Office
207 Plashet Grove
East Ham
E6 1BT
020 8430 2000