The Home Office have closed, by statutory instrument, the ability of EEA nationals and their family members who have acquired permanent residence in the UK from applying directly for British citizenship without first obtaining an EEA Permanent Residence document. Traditionally it was possible to simply skip the need to first apply to the Home Office EEA Caseworking team for a Permanent Residence Card. Permanent residence under the Citizen's Directive, and the regulations incorporating the Directive into UK law, is acquired by operation of law based on an objective position that the relevant requirements are met. As a result the documentation merely confirms a right which already exists. The Home Office in an EEA Permanent Residence application are not in effect deciding to grant some benefit using their discretion, they are merely giving documentary confirmation of a right which already exists.
As a result it was possible to just ignore that step, and in the case of an EEA national married to a British Citizen immediately apply for Citizenship, or in other cases wait for one year and then apply (the reason for this difference is linked to nationality law provisions).
In these cases an applicant would provide all of the evidence to say that they had acquired, by law, the right of permanent residence at a specific date, and the citizenship caseworking team in the Home Office would consider the case and evidence without insisting on a document confirming permanent residence issued by their colleagues.
This new statutory instrument changes that. From 12 November 2015 it will be necessary, where an applicant seeks to rely on a right of permanent residence in an application for British citizenship for them to provide a document confirming that right.
This will necessitate*, unfortunately, an application using form EEA (PR), which is now 85 pages long, to acquire a permanent residence document, before an application for citizenship can be made. This will add delay and complexity. The EEA Caseworking team at the moment is extremely slow.
Of course under EU law the Home Office do have restrictions on their ability to tinker with the operation of the free movement provisions, but with respect to British citizenship they are not so constrained, and can really impose whatever conditions they like, within reason.
These provisions do not appear to have any transitional element, which would seem to mean that they will take effect on 12 November regardless of whether an applicant has applied before that date.
Credit to Jonathan Kingham for spotting this change, which fell under my radar certainly.
* Actually completion of the form is not a legal requirement- but its probably best to comply