The Home Office have now got in touch to say they are extending the 20 working day response period (which ended today) in order to consider whether our request meets the public interest test. They write:
We are considering your information request. Although the Freedom of Information Act carries a presumption in favour of disclosure, it provides exemptions which may be used to refuse to confirm whether or not we hold information, or where we do, to withhold that information in specified circumstances. Some of these exemptions are subject to a public interest test. These exemptions are known as qualified exemptions. The public interest test is used to balance the public interest in openness against the public interest in favour of applying exemptions. Section 10(3) of the Act allows us to exceed the 20 working day response target where reasonably necessary to consider the public interest test fully. This is subject to us telling applicants when we expect to conclude our deliberations and provide a full response.
We are currently assessing the public interest in saying whether or not we hold the information you have requested, and should we do so, in providing the information you have requested. We are doing so under the exemptions contained in Sections 23(5) and 24(2) (national security), 35(3) (formulation of government policy, 31(3) (prevention and detection of crime) and 43(3) (prejudice to commercial interests) of the Freedom of Information Act.
This letter should not be taken as conclusive evidence that the information you have requested exists or does not exist."