The Office Of The Home
This would appear to be a bastardisation of The Home Office, a department of the pre-Fall UK civil service.
The Office of the Home is a paramilitary organisation, seemingly dedicated to finding and fostering communities that can restore civilisation to the United Kingdom. They seem to have at least partial control over the EMRIS satellite as they use it to communicate with their leadership, the Regent. They also have significant stores of military hardware and high level security clearances to access the DAHL archive. Where FEF personnel have applied for access themselves, it is the Office of the Home that appears to have granted it, or at least delivered the clearance itself.
The best guess is that the Regent is an AI, most likely the Guardian AI. It is also possible that the Regent is a system located in the Palace of Westminster. The Regent has been in charge for the entire existence of the Office of the Home, and whilst the knights have shown themselves capable of returning from the dead, it seems more likely the Regent is an AI.
The Knights are the backbone of the group. They travel around looking for pre-Fall artefacts and technology to preserve and restore, and for communitities that show promise with regard to restoring a greater sense of order and cviilisation to the UK.
The Knights seem to have the capability to return from the dead, although it appears they are slowly losing that ability. We do not currently know how this works but it is known that the knights have a chip at the base of their skulls that seems to record their consciousness and memories. The assumption is that as a knight dies, the chip is implanted into a new host and the personality takes over the new host body. How much of the host's original personality survives is unclear, but conversations with knights suggest that new versions of a knight do have different personality traits compared to the old.
The Scribes are the ones who catalogue and repair found technology, and keep the knight's equipment in good order. They are technically savvy and recruited for those abilities.
Knights are accompanied by a group of men-at-arms as a fighting force. Neither the men-at-arms nor the scribes have access to the personality chips.