VM delivers all BBC and ITV regional variants from its central headend at Langley. Regional headends don’t decide which region you receive — they simply broadcast whatever Langley provides. This also means that there is no configuration you can do from your box.
For set-top boxes (TiVo, V6 and 360), the BBC One and ITV1 region is controlled by a central mapping table at Langley that assigns the appropriate regional variant. If that mapping is changed or becomes incorrect, everyone will suddenly see different regional news.
Stream boxes work differently: the region is selected using account postcode and IP-based regionalisation, but again this is handled centrally rather than by the regional headends.
If the wrong region appears, it’s almost always a backend configuration issue that needs correcting by Langley. If you still have the problem I think it’s best raised via a forum staff member or VIP who can pass it to the right team.